Answer: 20
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Explanation:
The triangles are similar, allowing us to form a proportion
The vertical sides pair up on one side, the horizontal sides pair up on the other side. Divide in the same order.
QV/RT = VS/TS
5/3 = x/12
12*5 = 3x ... cross multiply
60 = 3x
3x = 60
x = 60/3
x = 20
VS = 20
