Electrical mathQuestion 479 of 1506

A right triangle has one angle of 35 degrees. What is the size of the third angle?

  1. 145 degrees
  2. 35 degrees
  3. 90 degrees
  4. 55 degrees
Show answer

Correct answer: 55 degrees

The three angles add to 180. The right angle is 90, so 180 - 90 - 35 = 55.

Source: Trigonometry and Single Phase AC Generation for Electricians (Flinn), 1.2: Triangles

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Questions last reviewed: 18 October 2026