Question

The length of a rectangle is five centimeters more than twice its width. The perimeter is 100 centimeters. Use Guess and Check to find out how long and how wide the rectangle is.

Answer 1

Guessing and checking isn't the best solution, so I will demonstrate it another way.

Let x be the width. We know that the length is then 2x+5.

So, 2(x+2x+5)=100

3x+5=50

3x=45

So, x=15.

Therefore, the rectangle is 15 centimeters wide.

Guessing and checking could also work. Once you plug in a value, if it is less than 100, than increase you number. The other way works as well.