A bit of a help please? Similar Rectangles

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1 Answer
May 9, 2017

#40.32cm^2#

Explanation:

So for the area we're going to need the longest side on the larger rectangle. As the rectangles are similar, the ratio of the sides is the same on both.
To work out the ratio we're going to do the unknown side/known side.
Therefore, #7/4 = 1.75#.
We can then times this by our shorter side on the larger rectangle:
#1.75xx4.8=8.4cm#.
Area of a rectangle #=# longest side #xx# shortest side.
Therefore:
#8.4xx4.8=40.32cm^2#