Answer:
Step-by-step explanation:
Rationalize the denominator of b. So, multiply the numerator and denominator by 

Now, find a +b

Combine like terms

Now find (a + b)²
(a +b)² = 

Hint: 
Hello.
The are answer is 4 or 3
<span>
3^2 = 7(3) - 12
9 = 21 - 12
9 = 9
</span>4^2 = 7(4) - 12
16 = 28 - 12
16 = 16
Have a nice day
The measure of <FCD is 77 degrees
<h3>Circle geometry</h3>
From the given diagram, we have the following:
m<FCD + 90 + m<F = 180 degrees
Given the following parameters
m<BEO = 13 degrees = m<F
Substitute into the formula:
m<FCD + 90 +13 = 180 degrees
m<FCD = 180 - 103
m<FCD = 77 degrees
Hence the measure of <FCD is 77 degrees
Learn more on circle geometry here; brainly.com/question/24375372