Answer:
The third angle measures 66°
Explanation:
If we look at the properties of triangles, we will know that all triangles have angles that, when added together, equal 180 degrees. Because we already know the measurement of two of the angles, all we have to do is add them up and subtract the sum by 180.
57+57=114
180-114=66
We got 66 as the measure of the last angle. Now, to make sure we have the right answer, we are going to check our work. We do this by adding together all of the angle measurements. If they all add up to 180, then we know we have the correct answer.
57+57+66=180
We were correct! Now we have the measurements of all three of the triangle's angles. Great job!
I hope this is easy to understand. Please let me know if you need any more help. Have a great morning!