Answer
a. $-\sqrt 2$
b. $7\sqrt 5$
Work Step by Step
a. We can simplify the expressions as follows:
= $7\sqrt 2 - 8\sqrt 2$
= $7\sqrt 2 - 8\sqrt 2$ (Factoring out $\sqrt 2$)
= $\sqrt 2 (7-8)$
= $\sqrt 2 *(-1)$
= $-\sqrt 2$
b. We can simplify the expressions as follows:
= $5\sqrt 5 + 2\sqrt 5$
= $\sqrt 5 * (5 + 2)$
= $7\sqrt 5$.
