the length and width of a rectangle whose length is 12 centimeters more than its width

Question

I'm solving for x 

Answer 1

Hi Andrea, let's try to solve this tricky problem:

 

 

• Area of a Rectangle (A_R) = length * width = l * w
• We'll call our "width" (w) value 'x' just to make things easier, since we don't know how long it is.
• We know that the length of the rectangle (l) is 12 centimeters more than its width, or "12 + x"

 

 

 

A_R = l x w      set up terms

 

= (12 + x) * (x)          plug in values for variables

 

= 12x + x²                multiply both together and distribute

 

 

 

This is as far as we can get without knowing the area of the rectangle. If we had the area, we could solve for 'x' and get the length and width.