X = 25.5 mm.
Using the similarity statement given, that ΔABC ~ ΔDEF, we set up a proportion:
8.5/x = 4/12
Cross multiply:
4*x = 8.5*12
4x = 102
Divide both sides by 4:
4x/4 = 102/4
x = 25.5
YOUR ANSWER IS A
HOPE THIS HELPS
(1,1) is your answer.
Work is shown below.
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