Question

Find the measure of two complementary angles, a and b, if m a = 7x + 4 and m b =4x + 9

Answer 1

Complentary angles add to 90 degrees
a and b are complentary
a+b=90

a=7x+4
b=4x+9
so
7x+4+4x+9=90
combine like terms
11x+13=90
minus 13 both sides
11x=77
divide both sides by 11
x=7

m a =7x+4=7(7)+4=49+4=53
m b=4x+9=4(7)+9=28+9=37

angle a measures 53 degrees
angle b measures 37 degrees

Answer 2

A would be 53 and b would be 37.
37 +53 =90 complementary angle =90°