The difference between the length and width of a rectangle is 7 centimeters. Find the dimensions of the rectangle if its perimeter is 50 centimeters. Write & solve a system of equations by substitution.

Question

whpalmer4 · Answer

What's the formula for the perimeter of a rectangle?  Write the formula, and set it equal to 50.

You know that length = width + 7 (or if you prefer, width = length + 7).  You can use either equation to substitute one variable for the other in the equation for the perimeter.  Now you have an equation in one variable to solve.  Once you do, you can determine the other one from the difference in lengths formula.

haltiamali · Answer

So, can you show me the equations so I can make sure I got them correct?

haltiamali · Answer

I have test over this tomorrow and I'm really confused. :I

whpalmer4 · Answer

Okay, let's let L be the length, W the width.

L = W + 7  (we'll decide that the length is the longer one)
What's the formula for the perimeter of a rectangle?