what is the missing angle in the triangle?

Explanation:

Step1: Recall angle - sum property

The sum of interior angles of a triangle is 180°.

Step2: Identify known angles

One angle is 30° and another is 90° (right - angle symbol).

Step3: Calculate the missing angle

Let the missing angle be (x). Then (x+30^{\circ}+90^{\circ}=180^{\circ}), so (x = 180^{\circ}-(30^{\circ}+90^{\circ})=60^{\circ}).

Answer:

60