SOLUTION: 1) the length of a rectangle is 3in more than its width. The perimeter of the rectangle is 30in

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Question 993198: 1) the length of a rectangle is 3in more than its width. The perimeter of the rectangle is 30in
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

let the length be L and the width W
if the length of a rectangle is 3in more than its width, than we have
L=W%2B3in....eq.1

if the perimeter of the rectangle is P=30in+, we have
2%28L%2BW%29=30in+....substitute L from eq.1
2%28W%2B3in%2BW%29=30in+.......solve for W
%282W%2B3in%29=30in%2F2+
2W%2B3in=15in+
2W=15in-3in+
2W=12in+
W=12in%2F2+
highlight%28W=6in%29+
go back to L=W%2B3in....eq.1 substitute 6in for substitute W and solve for substitute L
L=6in%2B3in
highlight%28L=9in%29