She still needs 36 inches of fabric (Also meaning 1 foot)
3/4(2x + 5) = 5(x + 12)
First get rid of any fractions by multiplying my the denominator
4 x 3/4(2x + 5) = 4 x 5(x + 12)
3(2x + 5) = 20(x + 12)
Then get rid of the parentheses
6x + 15 = 20x +240
Then simplify
6x + 15 - 15 = 20x + 240 - 15
6x = 20x + 225
6x - 20x = 20x - 20x + 225
-14x = 225
Now divide on both sides
-14x/-14 = 225/-14
x = -16
7 - 3 = 4....so there is a $ 4 profit for every unit sold
4x = 3600
x = 3600/4
x = 900....so 900 units have to be sold to earn a profit of $ 3600
