Question

each row contains the measures of 2 angles for a triangle. for each triangle, select the measure of the third angle. answers may be used more than once.
30° 40° 50°
40° and 100°
60° and 90°
15° and 75°
65° and 75°

Explanation:

Step1: Recall angle - sum property

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

Step2: Calculate for 40° and 100°

Let the third angle be \(x\). Then \(x = 180-(40 + 100)=40^{\circ}\).

Step3: Calculate for 60° and 90°

Let the third angle be \(y\). Then \(y=180-(60 + 90)=30^{\circ}\).

Step4: Calculate for 15° and 75°

Let the third angle be \(z\). Then \(z = 180-(15 + 75)=90^{\circ}\).

Step5: Calculate for 65° and 75°

Let the third angle be \(w\). Then \(w=180-(65 + 75)=40^{\circ}\).

Answer:

40° and 100°: 40°
60° and 90°: 30°
15° and 75°: 90°
65° and 75°: 40°