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# Help me solve a math equation please!?

Topic: Help me solve a math equation please!?
July 18, 2019 / By Bret
Question: Suppose that the width of a rectangle is 5 inches shorter than the length that the perimeter of the rectangle is 50 inches. The formula for the perimeter of the rectangle is P=2L+2W. a) Set up an equation involving only L, the length of the rectangle. b) What is the length? What is the width? (Please help me out! I'm swamped in work and this problem kinda stumped me >.< please and thank you)

Aherin | 10 days ago
a. W=L-5. P = 2L + 2W. Substitute W=L-5 and you get: P=2L + 2(L-5). Multiply 2 through the bracket and you get: P=2L + 2L - 10. Add the Ls and you get: P=4L-10. Add 10 to both sides and you get: P+10 = 4L. Divide both sides by 4 and L = (P+10)/4. b. P=50. Using the equation above for L: Put 50 in for P. L = (50+10)/4 = 60/4 = 15. From a, above, W=L-5 = 15-5 = 10. Answer. L=15. W=10 Proof of your work. P = 2L + 2W = 2x15 + 2x10 = 30 + 20 = 50
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