let say the number = x
double my number and add eight, I get my number plus twelve
double x and add eight, I get x plus twelve
2x + 8 = x + 12 (subtract x from each side)
2x - x + 8 = 12
x + 8 = 12 (subtract 8 from each side)
x = 12 - 8
x = 4
Your number is 4
