1. Angles of Triangles
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Consider the Exterior Angle Theorem.
130^(∘)
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. We see that ∠2 is exterior angle to ∠1. Therefore, we can equate it's measure with the sum of the two nonadjacent angles, 40^(∘) and 90^(∘).
The measure of ∠2 is 130^(∘).