∠uvw and ∠xyz are complementary angles, m∠uvw=(x−10)º , and m∠xyz=(4x−10)º .

we know that

if ∠UVW and ∠XYZ are complementary angles

then

∠UVW + ∠XYZ=90°

∠UVW=x-10

∠XYZ=4x-10

substitute the values

(x-10)°+(4x-10)°=90°

Solve for x

5x-20=90

5x=90+20

5x=110

x=22°

∠UVW=x-10=22-10=12°

∠XYZ=4x-10=4*22-10=78°

therefore

the answer is

x=22°

∠UVW=12°

∠XYZ=78°

Using the concept of complementary angles, it is found that:

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The measure of angle UVW is 12º.

The measure of angle XYZ is 78º.

A similar problem is given at link

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