How does an exterior angle of a triangle relate to the triangles two nonadjacent interior angles?
m∠1=130^(∘) Explanation: See solution
Practice makes perfect
According to the Exterior Angle Theorem, the measure of an exterior angle of a triangle is equal to the sum of the measures of the two nonadjacent interior angles. In this case, the two nonadjacent angles have been added to ∠1 and then equated with 180^(∘). What we instead want to do is to equate ∠1 with the sum of 80^(∘) and 50^(∘):
m∠1=80^(∘)+50^(∘)
By solving this equation, we can find m∠1.
