Question

find the measure of the third angle in each of the following triangles. the triangles are not drawn to scale.
a. the measure of the missing angle is °. (simplify your answer.)
b. the measure of the missing angle is °. (simplify your answer.)

Explanation:

Step1: Recall angle - sum property of a triangle

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

Step2: Calculate the missing angle for part a

Let the missing angle be $x$. We have $x + 50^{\circ}+70^{\circ}=180^{\circ}$. Then $x=180^{\circ}-(50^{\circ}+70^{\circ})=180^{\circ}-120^{\circ}=60^{\circ}$.

Step3: Calculate the missing angle for part b

Let the missing angle be $y$. Since one angle is 90° (right - angle) and another is 30°, we have $y + 90^{\circ}+30^{\circ}=180^{\circ}$. Then $y=180^{\circ}-(90^{\circ}+30^{\circ})=180^{\circ}-120^{\circ}=60^{\circ}$.

Answer:

a. 60
b. 60