Answer: x = 6
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Step-by-step explanation:
The jump from CD = 2 to C'D' = 4 is "times 2". That must mean we go from BC = 3 to B'C' = 2*(BC) = 2*3 = 6. Therefore, x = 6.
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We could use a proportion to get the value of x as an alternative method:
(B'C')/(BC) = (C'D')/(CD)
x/3 = 4/2
2x = 3*4 ... cross multiply
2x = 12
x = 12/2 .... dividing both sides by 2
x = 6