2.Alternate Interior angles theorem.
They given angles are alternate and interior when compared to each other, so they are congruent.
3 Vertical angles theorem.
The two angles are vertical angles and are not congruent.
4 Angle-Angle Similarity Postulate.
Because there are two corresponding angles that are congruent they are similar triangles by the angle-anlge similarity postulate.
Answer:
∠A = ∠B = 80°
Step-by-step explanation:
The angles are corresponding angles where a transversal crosses parallel lines, so are congruent. That means ...
∠A = ∠B
8x -8° = 5x +25° . . . . . substitute the given expressions
3x = 33° . . . . . . . . . . . . add 8°-5x
x = 11° . . . . . . . . . . . . . . divide by 3
Then the angles are ...
8·11° -8° = 80°
