Answer:
The answer is 60 degrees.
Step-by-step explanation:
The three angles in any triangle add up to 180 degrees.
You know by the box at the bottom right that it's a right triangle and therefore that angle is 90 degrees. They also give you the 30 degree angle at the bottom left. So:
90 degrees + 30 degrees = 120 degrees.
180 degrees (total) - 120 degrees (first 2 angles) = 60 degrees (missing angle)
Hope this helps!
