Answer: x = 30
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Explanation:
Due to the parallel lines, we have two similar triangles. So the sides are proportional.
18/27 = 20/x
2/3 = 20/x
2x = 3*20
2x = 60 .... cross multiply
x = 60/2
x = 30
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Another way you can approach it is to say
18/(18+27) = 20/(20+x)
18/45 = 20/(20+x)
2/5 = 20/(20+x)
2(20+x) = 5*20
40+2x = 100
2x = 100-40
2x = 60
x = 60/2
x = 30
