Question

∠C and ​ ∠D ​ are vertical angles with m∠C=−x+26 and m∠D=2x−10 .



What is m∠D ?

Answer 1

Vertical angles are equal.
Therefore,

-x + 26 = 2x - 10
3x = 36
x =12
Therefore, angle D = 14 degrees.