<PRE><B>Question 60671</B>
PERIMETER=2*LENGTH+2WIDTH
78=2*L+2(L-3)
78=2L+2L-6
78=4L-6
4L=78+6
4L=84
L=84/4
L=21 THEN THE WIDTH=21-3=18
PROOF
78=2*21+2*18
78=42+36
78=78
SUGGESTION: WHEN YOU WORK WORD PROBLEMS, IF POSSIBLE, DRAW A PICTURE, SKETCH OR DIAGRAM AND LABEL ALL RELEVENT FACTS, MEASUREMENTS, ANGLES, ETC.
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