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Isosceles Triangles and Triangle Sum Theorem

ACTMAT-JKT4IM

Triangle ABC is an isosceles triangle with vertex A and $AB = AC.$ Points D and E are placed on segments AB and AC, respectively, so that $CD = DE = AE.$ Refer to the figure below.

If the $ m{\angle }A = x $, what is $ m{\angle }BCD $ (in degrees) in terms of $x$?

A

$ {\cfrac { 1 }{ 2 } x} $

B

$x$

C

$ 90-{\cfrac { 1 }{ 2 } x} $

D

$ 90-{\cfrac { 5 }{ 2 } x} $

E

$ 90-{\cfrac { 7 }{ 2 } x} $