Respuesta :

apologiabiology
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
610032197

Answer: B. 7

Step-by-step explanation: