The length of the support piece is 6 inches
Solution:
The image of the problem is attached below.
Rosie is building a wheelchair ramp that is 12 feet long and 1.5 feet height.
Given, AD = 4 ft, AB = 12 ft, BC = 1.5 ft
Let us first convert feet into inches.
1 ft = 12 inches
AD = 4 ft × 12 = 48 inches
AB = 12 × 12 = 144 inches
BC = 1.5 × 12 = 18 inches
DB = AB – AD
= 144 inches – 48 inches
DB = 96 inches
ΔABC and ΔAED are similar triangles.
If two triangles are similar then their corresponding sides are in proportional.


Do cross multiplication, we get

Divide by 144 on both sides of the expression, we get
x = 6
The length of the support piece is 6 inches.