Prove that ΔABC ≅ ΔDEC
Then find the values of x and y.
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Prove That ΔABC ≅ ΔDEC
ΔABC ≅ ΔDEC because
DC = AC (1)
CE = CB (2)
Angle ACB = angle DCE(3)
So, both triangle are congruent according to SAS (Side, angle, side).