The length of the second rectangle is 30cm
<h3>When are two rectangles said to be similar?</h3>
Two rectangles are similar when the corresponding adjacent sides have the same ratio. We do not need to check the angles as all angles in a rectangle are 90 degrees.
all rectangles are not similar rectangles. The ratio of the corresponding adjacent sides may be different.
length the length and width of first rectangle be L1 and W1 and length and width of second rectangle be L2 and W2
then the ratio of length should be equal to ratio of width since both rectangles are similar
L1/L2 = W1/W2
L1 = 21cm, W1 = 14cm, W2 = 20cm
21/L2 = 14/20
cross multiply
14L2 = 420
L2 = 420/14
L2 = 30cm
In conclusion the length of second rectangle is 30cm
Learn more about similar rectangles: brainly.com/question/17905285
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