Question

A and B are complementary angles. If mA = (2x +27)° and mB =

(2x-21), then find the measure of A.

Answer 1

mA = 69 degrees

Explanation:

A complementary angle has a measure of 90 degrees.

(2x + 27) + (2x - 21) = 90

Simplify

4x + 6 = 90

-6

4x = 84

/4

x = 21

mA: 2(21) + 27 = 69

Answer 2

A = 69°

Explanation:

Complementary angles sum 90°

A + B = 90°

(2x + 27) + (2x-21) = 90°

4x + 27 - 21 = 90°

4x + 6 = 90°

4x = 90 - 6

4x = 84°

x = 84°/4

x = 21

Then A:

A = 2x + 27

A = 2*21 + 27

A = 42 + 27

A = 69°

B = 2x - 21

B = 2(21) + 27

B = 42 - 21

B = 21°

Check:

69 + 21 = 90