for what value of x is <1 complementary to <2, if m <1=5x+4 and m <2=7x+2. a. 3 b.7 c.1 d.14.5
complementary means adds to 90 degrees
so
∠1+∠2=90
given
∠1=5x+4 and
∠2=7x+2
so
∠1+∠2=90
5x+4+7x+2=90
5x+7x+4+2=90
12x+6=90
minus 6 both sides
12x=84
divide both sides by 12
x=7
answer is B