Does anyone minding helping me with exterior angles ? due in 2 days

see explanation

Step-by-step explanation:

The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.

∠ CBD is an exterior angle of the triangle, then

6x = x + 40 + 3x + 10, that is

6x = 4x + 50 ( subtract 4x from both sides )

2x = 50 ( divide both sides by 2 )

x = 25

Thus

∠ CBD = 6x = 6 × 25 = 150°

∠ CBA and ∠ CBD are adjacent angles and supplementary, sum to 180°, then

150° + ∠ CBA = 180° ( subtract 150° from both sides )

∠ CBA = 30°

b

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