∠a=8x−10 ∘ start color #11accd, angle, a, equals, 8, x, minus, 10, degrees, end color #11accd \qquad \green{\angle b=3x + 90^\circ} ∠b=3x+90 ∘

you answer is a

step-by-step explanation:

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

if i put something wrong your not gonna like it so rather not say nothing.