Question

for what value of x is <1 complementary to <2, ifm <1=5x+4 and m <2=7x+2 a.3 b7. c.1 d.14.5

Answer 1

Complementary angles are angles whose sum is equal to 90°.

m∠1 = 5x + 4
m∠2 = 7x + 2

m∠1 + m∠2 = 90°.

5x + 4 + 7x + 2 = 90
12x + 6 = 90
12x = 90 - 6
12x = 84
12x / 12 = 84/12
x = 7  Choice B.

m∠1 = 5x + 4 = 5(7) + 4 = 35 + 4 = 39
m∠2 = 7x + 2 = 7(7) + 2 = 49 + 2 = 51

39 + 51 = 90
90 =90