Answer:
40
Step-by-step explanation:
Let the number be y
-1/2 × y = -20
y = -20 ÷ -1/2
y = 20 × 2
y = 40
Multiply both sides by 3 to get:
3r = sqrt(A)
Square both sides:
9r^2 = A
In this question , it is given that
A painter charges by the square foot and charges you $1,875 to paint a 750 square foot rental house.
For 750 square foot, he charges $1875.
So for 1 square foot, he charges

And for 1300 square foot, he charges
