Ace the Jamaica Training Aid Test 2026 – Boost Your Skills and Shine Bright!

The interior angles of a triangle always add up to 180 degrees. One clear way to see this is to extend one side and draw a line parallel to it through the opposite vertex. The other two interior angles become alternate interior angles with angles along that parallel line, and together with the angle at the vertex they lie on a straight line, which totals 180 degrees. This aligns with the general polygon angle-sum formula (n−2)×180, which for a triangle (n = 3) gives 180 degrees. So the total of the three interior angles is 180 degrees, no matter the shape of the triangle. The other options don’t represent a sum of three interior angles: 90 degrees is just a single right angle, 360 degrees is a full turn or the sum of exterior angles, and 45 degrees is also just a single angle.