1) Since the angles are congruent, set them up to equal each other, then solve for x: x + 10 = 50. Now solve
2) Since angles AEC and DEB are congruent, set them up also to equal each other, then solve. : 6x + 20 = 10x. Now solve for x
3) Since AEC and DEB are congruent, they have the exact same angle measurement. Because of this, you are able to set the two equations equal to each other, then solve for x. After you have the value of x, you can plug it into 5x + 12 and solve once again, resulting in the answer for the measurement of angle AEC.