12. the measure of the angles of a triangle are represented by (x + 10), (2x + 20) and
(2x - 25). find the measure of all the angles.

12

step-by-step explanation:

a triangle's   full angle is 180 degrees so 180 - 156 = 24. 24/2=12

ca = ec

cpctc makes it so that corresponding parts of the triangle you proved to be equal are equal, the other options aren't part of the part of the triangles you proved to be equal.

but which class are u may know that first