.A triangle has one angle with an angle of 52 degrees and another of 39 degrees. What is the measure of the third angle?

89°

Step-by-step explanation:

The interior angles (angles inside) of a triangle must add up to 180 degrees.

We have 3 angles: 52 degrees, 39 degrees and x(unknown) degrees.

If we add all these angles together, they must equal 180 degrees.

52°+39°+x=180°

Combine like terms by adding 52 and 39

91°+x=180°

We want to find out what x, or the measure of the third angle is. In order to do this, we have to get x by itself. Perform the opposite of what is being done to the equation. Be sure to perform everything to both sides.

91 is being added to x. The opposite of addition is subtraction. Subtract 91 from both sides.

91°-91°+x=180°-91°

x=180°-91°

x=89°

The measure of the third angle in the triangle is 89 degrees.

c.

step-by-step explanation:

b

step-by-step explanation: