Let the three angles of the triangle be A, B, and C. We are given two angles, say A = 50^° and B = 30^°. We need to find the third angle, C. We can set up an equation using the angle sum property.

Now, substitute the given values of the two angles into the equation. We have 50^° for the first angle and 30^° for the second angle.

First, add the two known angles: 50^° + 30^° = 80^°. Then, subtract this sum from 180^° to find the measure of the third angle, C.

Two angles of a triangle are 50 and 30. What is the 3rd?

Answer: The third angle is $100^\circ$ .

Step-by-step solution

Step 1: Recall Angle Sum Property

A fundamental property of triangles states that the sum of the measures of its three interior angles is always equal to $180^\circ$ . This property is crucial for finding unknown angles within a triangle.

Step 2: Set up the equation

Let the three angles of the triangle be $A$ , $B$ , and $C$ . We are given two angles, say $A = 50^\circ$ and $B = 30^\circ$ . We need to find the third angle, $C$ . We can set up an equation using the angle sum property.

Step 3: Substitute known values

Now, substitute the given values of the two angles into the equation. We have $50^\circ$ for the first angle and $30^\circ$ for the second angle.

Step 4: Simplify and solve for C

First, add the two known angles: $50^\circ + 30^\circ = 80^\circ$ . Then, subtract this sum from $180^\circ$ to find the measure of the third angle, $C$ .

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