Answer:
The first questions unknown equals

The second question is unclear. I assume it is to simplify if that is the case the answer will be.

Explanation:
First Question I made ?=x for simplicity.

then I divide both sides by 7

then I square both sides

Question 2
I simplified by dividing both the denominator and the numerator by their HCF (highest common factor) which is 5

which equals
