1. The problem is to find the measure of the missing angle in a triangle where the other two angles are given as 149° and 87°. 2. The formula used is the Triangle Angle Sum Theorem, which states that the sum of the interior angles of a triangle is always 180°. 3. Let the missing angle be $x$. According to the theorem: $$149 + 87 + x = 180$$ 4. Add the known angles: $$236 + x = 180$$ 5. To isolate $x$, subtract 236 from both sides: $$x = 180 - 236$$ 6. Simplify the right side: $$x = -56$$ 7. Since an angle in a triangle cannot be negative, this indicates an error in the given angles because the sum of 149° and 87° already exceeds 180°, which is impossible for a triangle. Therefore, the given angles cannot form a triangle, and the missing angle cannot be determined with these values.