Please help me and give a real answer, it would help a lot.

What is the product of the radical expression. (7-2square root) (8+2 square root)

Acyclist bike x distance at 10 miles per hour .and returns over the same path at 8 miles per hour. what is the cyclist average rate for the round trip in miles per hour ?

1. ∠1 is complementary to ∠2 and ∠3 is complementary to ∠2. subtraction property of equality 2. m∠1 + m∠2 = 90 and m∠3 + m∠2 = 90 substitution 3. m∠1 + m∠2 = m∠3 + m∠2 definition of complementary 4. m∠1 = m∠3 given