A. 13
Step-by-step explanation:
What we are given....
∠A = 26° + x
∠B = 38° + x
∠A and ∠B are complementary
If complementary angles add up to equal 90° and ∠A and ∠B are complementary to each other
Then 26 + x + 38 + x = 90
^ ( Note that we just created an equation that we can use to solve for x )
Now its just basic algebra
26 + x + 38 + x = 90
step 1 combine like terms
26 + 38 = 64
x + x = 2x
we now have 64 + 2x = 90
step 2 subtract 64 from each side
64 - 64 cancels out
90 - 64 = 26
we now have 26 = 2x
step 3 divide each side by 2
26 / 2 = 13
2x / 2 = x
we're left with x = 13
