How do you combine $\sqrt{18} - \sqrt{8}$ $sqrt18-sqrt8$ ?

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Answer 1 · 2015-10-21T10:20:26

$\sqrt{2}$ $sqrt(2)$

$\sqrt{18} - \sqrt{8}$ $sqrt(18) - sqrt(8)$ ........................(1)

Write $\sqrt{18}$ $sqrt(18)" "$ as $\sqrt{2 \times 9} = 3 \sqrt{2}$ $sqrt(2 times 9) = 3 sqrt(2)$ .......(2)

Write $\sqrt{8}$ $sqrt(8) " "$ as $\sqrt{2 \times 4} = 2 \sqrt{2}$ $sqrt(2 times 4) = 2sqrt(2)$ .........(3)

Substitute (2) and (3) into (1) giving:

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

3 of something minus 2 of the same thing gives just one of the thing

So $3 \sqrt{2} - 2 \sqrt{2} = \sqrt{2}$ $" "3sqrt(2)-2sqrt(2)" " = " "sqrt(2)$

How do you combine √18−√8sqrt18-sqrt8?