Answer:
16
Step-by-step explanation:
Let the number = x
x + x/2 - 20 = 1/4 x
3/2 x - 20 = 1/4x Multiply by 4
3*2 x - 80 = x
6x - 80 = x
6x - x - 80 = 0
5x - 80 = 0
5x = 80
x = 16
Check
16 + 8 - 20 = 1/4 * 16
24 - 20 = 4
4 = 4
2 and 4
3
Each of the lines lengths multiply by 3.