Respuesta :

Answer:

Step-by-step explanation:

Supplementary angles mean the angles add up 90 degrees.

So, 4x + 18 + 2x + 12 = 90.

Combine like terms...

6x + 30 = 90

Subtract 30 from both sides.

6x = 60

Divide by 6

x = 10

Then to find the measure of angles RST, we plug in 10 for x.

4(10) + 18 = RST

RST = 40 + 18

RST = 58