Answer:
ZB= 39°
Step-by-step explanation:
complementary angles are angles that add up to equal 90
equation: 7x + 23 + 5x + 19 = 90
add like terms: 12x + 42 = 90
subtract 42 from both sides: 12x = 48
divide both sides by 12: x = 4
plug in the value of x to the equation for ZB: 5(4) + 19
simplify: ZB= 39°
