Answer:
x = 12
Step-by-step explanation:
Supplementary angles, sum = 180
10x - 20 + 6x + 8 = 180
16x - 12 = 180
16x = 192
x = 12
Let "x" be a substitute for "a number"
1/3(x)=x-12 Multiply by 3
x=3x-36 Get n onto the same side of the equation
2x=36 Divide by 2
x=18
That's your answer.
