So, since the polygons are similar, they will share a scale factor.
The dilation is a reduction.
SF= preimage/image
SF=48/40
SF= 1.2
To find the value of x, multiply 20 by 1.2, so:
20(1.2)=24
Thus, x = 24
Now, to check if the sides are proportional (this will determine if the polygons are, in fact, similar.)
24/20=1.2
48/40=1.2
BTW, the missing side measure for the image is 40 since 48 is its corresponding side, and 48/1.2 (SF) is 40.
Hence, we have 48/40= 1.2
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