How do you simplify 9sqrt 8 - sqrt72 + sqrt98?

1 Answer
Sep 8, 2016

19sqrt2

Explanation:

Write the numbers under the roots as the product of their prime factors.

9sqrt8 - sqrt72 + sqrt98

=9sqrt(2xx2xx2) - sqrt(2xx2xx2xx3xx3) + sqrt(7xx7xx2)

Find the square roots where possible

=9xx2sqrt2-2xx3sqrt2 +7sqrt2" "larr there is a common factor

=sqrt2(18-6+7)

=19sqrt2