Find area of the rectangle in terms of L.

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Question from Arlen, a student:

how do you find the length of a rectangle in terms of L?
for 6th grade question

this is the problem: The length of a rectangle is L. The width is 8 less than the length. Find area of the rectangle in terms of L.

Arlen,

Try it with numbers first keeping track of what you do.

Suppose the length is 12 inches, that is L = 12 inches.
The width is 8 less than the length so the width is 12 - 8 = 4 inches.
The area of the triangle is length times width which is 12 × 4 = 48 square inches.

Now again but without the specific value for L.

Suppose the length L inches.
The width is 8 less than the length so the width is L - 8 inches.
The area of the triangle is length times width which is L × (L - 8) square inches.

I hope this helps,
Penny

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