Final answer:
The measure of the third angle of the given isosceles triangle is 75 degrees.
Step-by-step explanation:
An isosceles triangle has two equal angles. Since the given triangle has two angles measuring 75 degrees, we can conclude that the other angle is also 75 degrees. This is because the sum of the angles of a triangle is always 180 degrees. If two angles are equal, their sum will be double that angle value.