What are the dimensions of a painting?

Question

marisol is painting on a canvas that has an area of 180 square inches. The length of the painting is 1 1/4 times the width. What are the dimensions of the painting?

Answer 1

Hello Pam

 

Let's begin with what we know.

 

The first sentence tells us

A = LW = 180 in²

 

The second sentence tells us

L = 1.25W

 

We can substitute the expression for L into the equation for the area and solve for the width

 

A = (1.25W) W = 180

1.25W² = 180

 

Dividing by 1.25

W² = 144

 

And taking the square root, 

W = ±12

 

Now a dimension cannot be a negative number, so W = 12

 

Now if W = 12 and L = 1.25W, then 

L = 1.25(12) = 15

 

The dimensions of the painting are 15" by 12".