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Add and Subtract Square Roots

Add and subtract like square roots

Add and Subtract Like Square Roots

Think about adding like terms with variables as you do the next few examples. When you have like radicands, you just add or subtract the coefficients. When the radicands are not like, you cannot combine the terms.

Example

Try it.

Simplify: \(2\sqrt{2}-7\sqrt{2}\).

Solution

\(2\sqrt{2}-7\sqrt{2}\)
Since the radicals are like, we subtract the coefficients.\(-5\sqrt{2}\)

Example

Try it.

Simplify: \(3\sqrt{y}+4\sqrt{y}\).

Solution

\(3\sqrt{y}+4\sqrt{y}\)
Since the radicals are like, we add the coefficients.\(7\sqrt{y}\)

Example

Try it.

Simplify: \(4\sqrt{x}-2\sqrt{y}\).

Solution

\(4\sqrt{x}-2\sqrt{y}\)
Since the radicals are not like, we cannot
subtract them. We leave the expression as is.		\(4\sqrt{x}-2\sqrt{y}\)

Example

Try it.

Simplify: \(5\sqrt{13}+4\sqrt{13}+2\sqrt{13}\).

Solution

\(5\sqrt{13}+4\sqrt{13}+2\sqrt{13}\)
Since the radicals are like, we add the coefficients.\(11\sqrt{13}\)

Example

Try it.

Simplify: \(2\sqrt{6}-6\sqrt{6}+3\sqrt{3}\).

Solution

\(2\sqrt{6}-6\sqrt{6}+3\sqrt{3}\)
Since the first two radicals are like, we
subtract their coefficients.		\(-4\sqrt{6}+3\sqrt{3}\)

Example

Try it.

Simplify: \(2\sqrt{5n}-6\sqrt{5n}+4\sqrt{5n}\).

Solution

\(2\sqrt{5n}-6\sqrt{5n}+4\sqrt{5n}\)
Since the radicals are like, we combine them.\(0\sqrt{5n}\)
Simplify.0

When radicals contain more than one variable, as long as all the variables and their exponents are identical, the radicals are like.

Example

Try it.

Simplify: \(\sqrt{3xy}+5\sqrt{3xy}-4\sqrt{3xy}\).

Solution

\(\sqrt{3xy}+5\sqrt{3xy}-4\sqrt{3xy}\)
Since the radicals are like, we combine them.\(2\sqrt{3xy}\)

Add and Subtract Square Roots that Need Simplification

Remember that we always simplify square roots by removing the largest perfect-square factor. Sometimes when we have to add or subtract square roots that do not appear to have like radicals, we find like radicals after simplifying the square roots.

Example

Try it.

Simplify: \(\sqrt{20}+3\sqrt{5}\).

Solution

\(\sqrt{20}+3\sqrt{5}\)
Simplify the radicals, when possible.\(\sqrt{4}\cdot \sqrt{5}+3\sqrt{5}\)
\(2\sqrt{5}+3\sqrt{5}\)
Combine the like radicals.\(5\sqrt{5}\)

Example

Try it.

Simplify: \(\sqrt{48}-\sqrt{75}\).

Solution

\(\sqrt{48}-\sqrt{75}\)
Simplify the radicals.\(\sqrt{16}\cdot \sqrt{3}-\sqrt{25}\cdot \sqrt{3}\)
\(4\sqrt{3}-5\sqrt{3}\)
Combine the like radicals.\(\text{-}\sqrt{3}\)

Just like we use the Associative Property of Multiplication to simplify \(5(3x)\) and get \(15x\), we can simplify \(5(3\sqrt{x})\) and get \(15\sqrt{x}\). We will use the Associative Property to do this in the next example.

Example

Try it.

Simplify: \(5\sqrt{18}-2\sqrt{8}\).

Solution

\(5\sqrt{18}-2\sqrt{8}\)
Simplify the radicals.\(5\cdot \sqrt{9}\cdot \sqrt{2}-2\cdot \sqrt{4}\cdot \sqrt{2}\)
\(5\cdot 3\cdot \sqrt{2}-2\cdot 2\cdot \sqrt{2}\)
\(15\sqrt{2}-4\sqrt{2}\)
Combine the like radicals.\(11\sqrt{2}\)

Example

Try it.

Simplify: \(\frac{3}{4}\sqrt{192}-\frac{5}{6}\sqrt{108}\).

Solution

\(\frac{3}{4}\sqrt{192}-\frac{5}{6}\sqrt{108}\)
Simplify the radicals.\(\frac{3}{4}\sqrt{64}\cdot \sqrt{3}-\frac{5}{6}\sqrt{36}\cdot \sqrt{3}\)
\(\frac{3}{4}\cdot 8\cdot \sqrt{3}-\frac{5}{6}\cdot 6\cdot \sqrt{3}\)
\(6\sqrt{3}-5\sqrt{3}\)
Combine the like radicals.\(\sqrt{3}\)

Example

Try it.

Simplify: \(\frac{2}{3}\sqrt{48}-\frac{3}{4}\sqrt{12}\).

Solution

\(\frac{2}{3}\sqrt{48}-\frac{3}{4}\sqrt{12}\)
Simplify the radicals.\(\frac{2}{3}\sqrt{16}\cdot \sqrt{3}-\frac{3}{4}\sqrt{4}\cdot \sqrt{3}\)
\(\frac{2}{3}\cdot 4\cdot \sqrt{3}-\frac{3}{4}\cdot 2\cdot \sqrt{3}\)
\(\frac{8}{3}\sqrt{3}-\frac{3}{2}\sqrt{3}\)
Find a common denominator to subtract the
coefficients of the like radicals.		\(\frac{16}{6}\sqrt{3}-\frac{9}{6}\sqrt{3}\)
Simplify.\(\frac{7}{6}\sqrt{3}\)

Condensed: the full section is in OpenStax Elementary Algebra 2e.

Key Concepts

  • To add or subtract like square roots, add or subtract the coefficients and keep the like square root.
  • Sometimes when we have to add or subtract square roots that do not appear to have like radicals, we find like radicals after simplifying the square roots.

Add and Subtract Square Roots

Add and Subtract Like Square Roots

In the following exercises, simplify.

Try it.

\(8\sqrt{2}-5\sqrt{2}\)

Solution

\(3\sqrt{2}\)

Try it.

\(7\sqrt{2}-3\sqrt{2}\)

Try it.

\(3\sqrt{5}+6\sqrt{5}\)

Solution

\(9\sqrt{5}\)

Try it.

\(4\sqrt{5}+8\sqrt{5}\)

Try it.

\(9\sqrt{7}-10\sqrt{7}\)

Solution

\(\text{-}\sqrt{7}\)

Try it.

\(11\sqrt{7}-12\sqrt{7}\)

Try it.

\(7\sqrt{y}+2\sqrt{y}\)

Solution

\(9\sqrt{y}\)

Try it.

\(9\sqrt{n}+3\sqrt{n}\)

Try it.

\(\sqrt{a}-4\sqrt{a}\)

Solution

\(-3\sqrt{a}\)

Try it.

\(\sqrt{b}-6\sqrt{b}\)

Try it.

\(5\sqrt{c}+2\sqrt{c}\)

Solution

\(7\sqrt{c}\)

Try it.

\(7\sqrt{d}+2\sqrt{d}\)

Try it.

\(8\sqrt{a}-2\sqrt{b}\)

Solution

\(8\sqrt{a}-2\sqrt{b}\)

Try it.

\(5\sqrt{c}-3\sqrt{d}\)

Try it.

\(5\sqrt{m}+\sqrt{n}\)

Solution

\(5\sqrt{m}+\sqrt{n}\)

Try it.

\(\sqrt{n}+3\sqrt{p}\)

Try it.

\(8\sqrt{7}+2\sqrt{7}+3\sqrt{7}\)

Solution

\(13\sqrt{7}\)

Try it.

\(6\sqrt{5}+3\sqrt{5}+\sqrt{5}\)

Try it.

\(3\sqrt{11}+2\sqrt{11}-8\sqrt{11}\)

Solution

\(-3\sqrt{11}\)

Try it.

\(2\sqrt{15}+5\sqrt{15}-9\sqrt{15}\)

Try it.

\(3\sqrt{3}-8\sqrt{3}+7\sqrt{5}\)

Solution

\(-5\sqrt{3}+7\sqrt{5}\)

Try it.

\(5\sqrt{7}-8\sqrt{7}+6\sqrt{3}\)

Try it.

\(6\sqrt{2}+2\sqrt{2}-3\sqrt{5}\)

Solution

\(8\sqrt{2}-3\sqrt{5}\)

Try it.

\(7\sqrt{5}+\sqrt{5}-8\sqrt{10}\)

Try it.

\(3\sqrt{2a}-4\sqrt{2a}+5\sqrt{2a}\)

Solution

\(4\sqrt{2a}\)

Try it.

\(\sqrt{11b}-5\sqrt{11b}+3\sqrt{11b}\)

Try it.

\(8\sqrt{3c}+2\sqrt{3c}-9\sqrt{3c}\)

Solution

\(\sqrt{3c}\)

Try it.

\(3\sqrt{5d}+8\sqrt{5d}-11\sqrt{5d}\)

Try it.

\(5\sqrt{3ab}+\sqrt{3ab}-2\sqrt{3ab}\)

Solution

\(4\sqrt{3ab}\)

Try it.

\(8\sqrt{11cd}+5\sqrt{11cd}-9\sqrt{11cd}\)

Try it.

\(2\sqrt{pq}-5\sqrt{pq}+4\sqrt{pq}\)

Solution

\(\sqrt{pq}\)

Try it.

\(11\sqrt{2rs}-9\sqrt{2rs}+3\sqrt{2rs}\)

Add and Subtract Square Roots that Need Simplification

In the following exercises, simplify.

Try it.

\(\sqrt{50}+4\sqrt{2}\)

Solution

\(9\sqrt{2}\)

Try it.

\(\sqrt{48}+2\sqrt{3}\)

Try it.

\(\sqrt{80}-3\sqrt{5}\)

Solution

\(\sqrt{5}\)

Try it.

\(\sqrt{28}-4\sqrt{7}\)

Try it.

\(\sqrt{27}-\sqrt{75}\)

Solution

\(-2\sqrt{3}\)

Try it.

\(\sqrt{72}-\sqrt{98}\)

Try it.

\(\sqrt{48}+\sqrt{27}\)

Solution

\(7\sqrt{3}\)

Try it.

\(\sqrt{45}+\sqrt{80}\)

Try it.

\(2\sqrt{50}-3\sqrt{72}\)

Solution

\(-8\sqrt{2}\)

Try it.

\(3\sqrt{98}-\sqrt{128}\)

Try it.

\(2\sqrt{12}+3\sqrt{48}\)

Solution

\(16\sqrt{3}\)

Try it.

\(4\sqrt{75}+2\sqrt{108}\)

Try it.

\(\frac{2}{3}\sqrt{72}+\frac{1}{5}\sqrt{50}\)

Solution

\(5\sqrt{2}\)

Try it.

\(\frac{2}{5}\sqrt{75}+\frac{3}{4}\sqrt{48}\)

Try it.

\(\frac{1}{2}\sqrt{20}-\frac{2}{3}\sqrt{45}\)

Solution

\(\text{-}\sqrt{5}\)

Try it.

\(\frac{2}{3}\sqrt{54}-\frac{3}{4}\sqrt{96}\)

Try it.

\(\frac{1}{6}\sqrt{27}-\frac{3}{8}\sqrt{48}\)

Solution

\(\text{-}\sqrt{3}\)

Try it.

\(\frac{1}{8}\sqrt{32}-\frac{1}{10}\sqrt{50}\)

Try it.

\(\frac{1}{4}\sqrt{98}-\frac{1}{3}\sqrt{128}\)

Solution

\(-\frac{11}{12}\sqrt{2}\)

Try it.

\(\frac{1}{3}\sqrt{24}+\frac{1}{4}\sqrt{54}\)

Try it.

\(\sqrt{72{a}^{5}}-\sqrt{50{a}^{5}}\)

Solution

\({a}^{2}\sqrt{2a}\)

Try it.

\(\sqrt{48{b}^{5}}-\sqrt{75{b}^{5}}\)

Try it.

\(\sqrt{80{c}^{7}}-\sqrt{20{c}^{7}}\)

Solution

\(2{c}^{3}\sqrt{5c}\)

Try it.

\(\sqrt{96{d}^{9}}-\sqrt{24{d}^{9}}\)

Try it.

\(9\sqrt{80{p}^{4}}-6\sqrt{98{p}^{4}}\)

Solution

\(36{p}^{2}\sqrt{5}-42{p}^{2}\sqrt{2}\)

Try it.

\(8\sqrt{72{q}^{6}}-3\sqrt{75{q}^{6}}\)

Try it.

\(2\sqrt{50{r}^{8}}+4\sqrt{54{r}^{8}}\)

Solution

\(10{r}^{4}\sqrt{2}+12{r}^{4}\sqrt{6}\)

Try it.

\(5\sqrt{27{s}^{6}}+2\sqrt{20{s}^{6}}\)

Try it.

\(3\sqrt{20{x}^{2}}-4\sqrt{45{x}^{2}}+5x\sqrt{80}\)

Solution

\(14x\sqrt{5}\)

Try it.

\(2\sqrt{28{x}^{2}}-\sqrt{63{x}^{2}}+6x\sqrt{7}\)

Try it.

\(3\sqrt{128{y}^{2}}+4y\sqrt{162}-8\sqrt{98{y}^{2}}\)

Solution

\(4y\sqrt{2}\)

Try it.

\(3\sqrt{75{y}^{2}}+8y\sqrt{48}-\sqrt{300{y}^{2}}\)

Mixed Practice

Try it.

\(2\sqrt{8}+6\sqrt{8}-5\sqrt{8}\)

Solution

\(6\sqrt{2}\)

Try it.

\(\frac{2}{3}\sqrt{27}+\frac{3}{4}\sqrt{48}\)

Try it.

\(\sqrt{175{k}^{4}}-\sqrt{63{k}^{4}}\)

Solution

\(2{k}^{2}\sqrt{7}\)

Try it.

\(\frac{5}{6}\sqrt{162}+\frac{3}{16}\sqrt{128}\)

Try it.

\(2\sqrt{363}-2\sqrt{300}\)

Solution

\(2\sqrt{3}\)

Try it.

\(\sqrt{150}+4\sqrt{6}\)

Try it.

\(9\sqrt{2}-8\sqrt{2}\)

Solution

\(\sqrt{2}\)

Try it.

\(5\sqrt{x}-8\sqrt{y}\)

Try it.

\(8\sqrt{13}-4\sqrt{13}-3\sqrt{13}\)

Solution

\(\sqrt{13}\)

Try it.

\(5\sqrt{12{c}^{4}}-3\sqrt{27{c}^{6}}\)

Try it.

\(\sqrt{80{a}^{5}}-\sqrt{45{a}^{5}}\)

Solution

\({a}^{2}\sqrt{5a}\)

Try it.

\(\frac{3}{5}\sqrt{75}-\frac{1}{4}\sqrt{48}\)

Try it.

\(21\sqrt{19}-2\sqrt{19}\)

Solution

\(19\sqrt{19}\)

Try it.

\(\sqrt{500}+\sqrt{405}\)

Try it.

\(\frac{5}{6}\sqrt{27}+\frac{5}{8}\sqrt{48}\)

Solution

\(5\sqrt{3}\)

Try it.

\(11\sqrt{11}-10\sqrt{11}\)

Try it.

\(\sqrt{75}-\sqrt{108}\)

Solution

\(\text{-}\sqrt{3}\)

Try it.

\(2\sqrt{98}-4\sqrt{72}\)

Try it.

\(4\sqrt{24{x}^{2}}-\sqrt{54{x}^{2}}+3x\sqrt{6}\)

Solution

\(8x\sqrt{6}\)

Try it.

\(8\sqrt{80{y}^{6}}-6\sqrt{48{y}^{6}}\)

Condensed: the full section is in OpenStax Elementary Algebra 2e.

Τώρα εσύ. Κανένας υπολογιστής δεν τακτοποιεί αυτό το ένα, αλλά τα κομμάτια του είναι ακλόνητα.

Πρακτική (40)

Αποκάλυψτε την απάντησι για να ελέγχετε · τα επαληθευμένα μπορούν ν'ανοίξουν στον λύτη για κάθε βήμα.

  1. Add: ⓐ \(3x+9x\) ⓑ \(5m+5n\).

    Αποκάλυψέ την.

    ⓐ \(12x\) ⓑ \(5m+5n\)

  2. Simplify: \(\sqrt{50{x}^{3}}\).

    Αποκάλυψέ την.

    \(5x\sqrt{2x}\)

  3. Simplify: \(2\sqrt{2}-7\sqrt{2}\).

    Αποκάλυψέ την.

    \(2\sqrt{2}-7\sqrt{2}\)
    Since the radicals are like, we subtract the coefficients.\(-5\sqrt{2}\)

  4. Simplify: \(8\sqrt{2}-9\sqrt{2}\).

    Αποκάλυψέ την.

    \(\text{-}\sqrt{2}\)

  5. Simplify: \(5\sqrt{3}-9\sqrt{3}\).

    Αποκάλυψέ την.

    \(-4\sqrt{3}\)

  6. Simplify: \(3\sqrt{y}+4\sqrt{y}\).

    Αποκάλυψέ την.

    \(3\sqrt{y}+4\sqrt{y}\)
    Since the radicals are like, we add the coefficients.\(7\sqrt{y}\)

  7. Simplify: \(2\sqrt{x}+7\sqrt{x}\).

    Αποκάλυψέ την.

    \(9\sqrt{x}\)

  8. Simplify: \(5\sqrt{u}+3\sqrt{u}\).

    Αποκάλυψέ την.

    \(8\sqrt{u}\)

  9. Simplify: \(4\sqrt{x}-2\sqrt{y}\).

    Αποκάλυψέ την.

    \(4\sqrt{x}-2\sqrt{y}\)
    Since the radicals are not like, we cannot
    subtract them. We leave the expression as is.    		\(4\sqrt{x}-2\sqrt{y}\)

  10. Simplify: \(7\sqrt{p}-6\sqrt{q}\).

    Αποκάλυψέ την.

    \(7\sqrt{p}-6\sqrt{q}\)

  11. Simplify: \(6\sqrt{a}-3\sqrt{b}\).

    Αποκάλυψέ την.

    \(6\sqrt{a}-3\sqrt{b}\)

  12. Simplify: \(5\sqrt{13}+4\sqrt{13}+2\sqrt{13}\).

    Αποκάλυψέ την.

    \(5\sqrt{13}+4\sqrt{13}+2\sqrt{13}\)
    Since the radicals are like, we add the coefficients.\(11\sqrt{13}\)

  13. Simplify: \(4\sqrt{11}+2\sqrt{11}+3\sqrt{11}\).

    Αποκάλυψέ την.

    \(9\sqrt{11}\)

  14. Simplify: \(6\sqrt{10}+2\sqrt{10}+3\sqrt{10}\).

    Αποκάλυψέ την.

    \(11\sqrt{10}\)

  15. Simplify: \(2\sqrt{6}-6\sqrt{6}+3\sqrt{3}\).

    Αποκάλυψέ την.

    \(2\sqrt{6}-6\sqrt{6}+3\sqrt{3}\)
    Since the first two radicals are like, we
    subtract their coefficients.    		\(-4\sqrt{6}+3\sqrt{3}\)

  16. Simplify: \(5\sqrt{5}-4\sqrt{5}+2\sqrt{6}\).

    Αποκάλυψέ την.

    \(\sqrt{5}+2\sqrt{6}\)

  17. Simplify: \(3\sqrt{7}-8\sqrt{7}+2\sqrt{5}\).

    Αποκάλυψέ την.

    \(-5\sqrt{7}+2\sqrt{5}\)

  18. Simplify: \(2\sqrt{5n}-6\sqrt{5n}+4\sqrt{5n}\).

    Αποκάλυψέ την.

    \(2\sqrt{5n}-6\sqrt{5n}+4\sqrt{5n}\)
    Since the radicals are like, we combine them.\(0\sqrt{5n}\)
    Simplify.0

  19. Simplify: \(\sqrt{7x}-7\sqrt{7x}+4\sqrt{7x}\).

    Αποκάλυψέ την.

    \(-2\sqrt{7x}\)

  20. Simplify: \(4\sqrt{3y}-7\sqrt{3y}+2\sqrt{3y}\).

    Αποκάλυψέ την.

    \(\text{-}\sqrt{3y}\)

  21. Simplify: \(\sqrt{3xy}+5\sqrt{3xy}-4\sqrt{3xy}\).

    Αποκάλυψέ την.

    \(\sqrt{3xy}+5\sqrt{3xy}-4\sqrt{3xy}\)
    Since the radicals are like, we combine them.\(2\sqrt{3xy}\)

  22. Simplify: \(\sqrt{5xy}+4\sqrt{5xy}-7\sqrt{5xy}\).

    Αποκάλυψέ την.

    \(-2\sqrt{5xy}\)

  23. Simplify: \(3\sqrt{7mn}+\sqrt{7mn}-4\sqrt{7mn}\).

    Αποκάλυψέ την.

    \(0\)

  24. Simplify: \(\sqrt{20}+3\sqrt{5}\).

    Αποκάλυψέ την.

    \(\sqrt{20}+3\sqrt{5}\)
    Simplify the radicals, when possible.\(\sqrt{4}\cdot \sqrt{5}+3\sqrt{5}\)
    \(2\sqrt{5}+3\sqrt{5}\)
    Combine the like radicals.\(5\sqrt{5}\)

  25. Simplify: \(\sqrt{18}+6\sqrt{2}\).

    Αποκάλυψέ την.

    \(9\sqrt{2}\)

  26. Simplify: \(\sqrt{27}+4\sqrt{3}\).

    Αποκάλυψέ την.

    \(7\sqrt{3}\)

  27. Simplify: \(\sqrt{48}-\sqrt{75}\).

    Αποκάλυψέ την.

    \(\sqrt{48}-\sqrt{75}\)
    Simplify the radicals.\(\sqrt{16}\cdot \sqrt{3}-\sqrt{25}\cdot \sqrt{3}\)
    \(4\sqrt{3}-5\sqrt{3}\)
    Combine the like radicals.\(\text{-}\sqrt{3}\)

  28. Simplify: \(\sqrt{32}-\sqrt{18}\).

    Αποκάλυψέ την.

    \(\sqrt{2}\)

  29. Simplify: \(\sqrt{20}-\sqrt{45}\).

    Αποκάλυψέ την.

    \(\text{-}\sqrt{5}\)

  30. Simplify: \(5\sqrt{18}-2\sqrt{8}\).

    Αποκάλυψέ την.

    \(5\sqrt{18}-2\sqrt{8}\)
    Simplify the radicals.\(5\cdot \sqrt{9}\cdot \sqrt{2}-2\cdot \sqrt{4}\cdot \sqrt{2}\)
    \(5\cdot 3\cdot \sqrt{2}-2\cdot 2\cdot \sqrt{2}\)
    \(15\sqrt{2}-4\sqrt{2}\)
    Combine the like radicals.\(11\sqrt{2}\)

  31. Simplify: \(4\sqrt{27}-3\sqrt{12}\).

    Αποκάλυψέ την.

    \(6\sqrt{3}\)

  32. Simplify: \(3\sqrt{20}-7\sqrt{45}\).

    Αποκάλυψέ την.

    \(-15\sqrt{5}\)

  33. Simplify: \(\frac{3}{4}\sqrt{192}-\frac{5}{6}\sqrt{108}\).

    Αποκάλυψέ την.

    \(\frac{3}{4}\sqrt{192}-\frac{5}{6}\sqrt{108}\)
    Simplify the radicals.\(\frac{3}{4}\sqrt{64}\cdot \sqrt{3}-\frac{5}{6}\sqrt{36}\cdot \sqrt{3}\)
    \(\frac{3}{4}\cdot 8\cdot \sqrt{3}-\frac{5}{6}\cdot 6\cdot \sqrt{3}\)
    \(6\sqrt{3}-5\sqrt{3}\)
    Combine the like radicals.\(\sqrt{3}\)

  34. Simplify: \(\frac{2}{3}\sqrt{108}-\frac{5}{7}\sqrt{147}\).

    Αποκάλυψέ την.

    \(\text{-}\sqrt{3}\)

  35. Simplify: \(\frac{3}{5}\sqrt{200}-\frac{3}{4}\sqrt{128}\).

    Αποκάλυψέ την.

    \(0\)

  36. Simplify: \(\frac{2}{3}\sqrt{48}-\frac{3}{4}\sqrt{12}\).

    Αποκάλυψέ την.

    \(\frac{2}{3}\sqrt{48}-\frac{3}{4}\sqrt{12}\)
    Simplify the radicals.\(\frac{2}{3}\sqrt{16}\cdot \sqrt{3}-\frac{3}{4}\sqrt{4}\cdot \sqrt{3}\)
    \(\frac{2}{3}\cdot 4\cdot \sqrt{3}-\frac{3}{4}\cdot 2\cdot \sqrt{3}\)
    \(\frac{8}{3}\sqrt{3}-\frac{3}{2}\sqrt{3}\)
    Find a common denominator to subtract the
    coefficients of the like radicals.    		\(\frac{16}{6}\sqrt{3}-\frac{9}{6}\sqrt{3}\)
    Simplify.\(\frac{7}{6}\sqrt{3}\)

  37. Simplify: \(\frac{2}{5}\sqrt{32}-\frac{1}{3}\sqrt{8}\).

    Αποκάλυψέ την.

    \(\frac{14}{15}\sqrt{2}\)

  38. Simplify: \(\frac{1}{3}\sqrt{80}-\frac{1}{4}\sqrt{125}\).

    Αποκάλυψέ την.

    \(\frac{1}{12}\sqrt{5}\)

  39. Simplify: \(\sqrt{18{n}^{5}}-\sqrt{32{n}^{5}}\).

    Αποκάλυψέ την.

    \(\sqrt{18{n}^{5}}-\sqrt{32{n}^{5}}\)
    Simplify the radicals.\(\sqrt{9{n}^{4}}\cdot \sqrt{2n}-\sqrt{16{n}^{4}}\cdot \sqrt{2n}\)
    \(3{n}^{2}\sqrt{2n}-4{n}^{2}\sqrt{2n}\)
    Combine the like radicals.\(\text{-}{n}^{2}\sqrt{2n}\)

  40. Simplify: \(\sqrt{32{m}^{7}}-\sqrt{50{m}^{7}}\).

    Αποκάλυψέ την.

    \(\text{-}{m}^{3}\sqrt{2m}\)

Να δουλεύεις μόνος σου.

Ένας δωρεάν λογαριασμός προσθέτει σημειώσεις σε κάθε μάθημα, ένα αρχείο του τι έχετε τελειώσει, λύθηκαν προβλήματα σας σε ένα μέρος, και ένας δάσκαλος που μπορείτε να ρωτήσετε για αυτή τη σελίδα.

Υπογράψτε Σύνδεση

Σύμβολα που χρησιμοποιούνται εδώ

Χτυπήστε οποιοδήποτε σύμβολο για τον πλήρη ορισμό, μια εικόνα, και τι σημαίνει κάθε γράμμα σε αυτό.

Πώς να: Add and Subtract Square Roots

  1. Add and subtract like square roots
  2. Add and subtract square roots that need simplification
  3. To add or subtract like square roots, add or subtract the coefficients and keep the like square root.
  4. Sometimes when we have to add or subtract square roots that do not appear to have like radicals, we find like radicals after simplifying the square roots.

Ερωτήσεις που κάνουν οι άνθρωποι

What does it mean to solve an equation?

To find every value of the unknown that makes both sides equal. Each step is an operation applied to both sides that keeps the solution set the same, until the unknown stands alone.

Why do I sometimes get two answers?

A quadratic can cross the axis twice, so it can have two solutions. A degree-n polynomial has up to n. The graph shows where each one comes from.

How do I know whether to factor or use the quadratic formula?

Try factoring for a few seconds: look for two numbers that multiply to a·c and add to b. If nothing obvious appears, the discriminant b² − 4ac tells you how many real roots there are, and the formula finds them without guessing.

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