The length of a rectangle is 7 more than the width, and the perimeter is 38. What is the width and length?

Question

mathmale · Answer

Choose letters to represent the length and width of the rectangle.  I would choose l and w for obvious reasons.   Now, write the relationship that shows how the length (l) depends upon the width (w).

ben00 · Answer

Do 7 x 2 and do it minus 38?

studyx3 · Answer

@mathmale would it be L+L+W+7+W+7=38?

mathmale · Answer

Your formula for the perimeter of the rectangle is a step in the right direction.  You are apparently substituting W + 7 for L (which is correct).  But you then have an expression for L + L + L + L, which is not correct.

Think:  how could you eliminate either L or W?  I'd suggest you eliminate L and keep W.

Start with L=W+7 and substitute this for L in the expression 2W + 2L = 38.