Answer: p = 1.4
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Explanation:
JK = LM because opposite sides of a parallelogram are the same length.
Side LM is p units long, where p is a placeholder for a number.
To determine what number replaces p, we can form the proportion shown below
BC/KL = CD/LM
Refer to the drawing below. I've circled the corresponding pieces. Note the color coding. Other equations are possible.
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So,
BC/KL = CD/LM
(5.1)/(1.7) = (4.2)/p
5.1p = 1.7*4.2 ....................... cross multiply
5.1p = 7.14
p = (7.14)/(5.1)
p = 1.4
