Answer:
The congruent sides are 80 degrees, the large angle it 160 degrees, and the smallest angle is 40 degrees.
Step-by-step explanation:
It is a quadrilateral, so the angles must add up to 360. 80 + 80 = 160, 160 + 160 = 320. 40 + 320 = 360.
Equation: (a = angle of congruent angle) 2a + a + a + (a/2) = 360. That should be a perfect answer.