Final answer:
The measure of the third angle in a triangle with angles measuring 45 and 90 degrees is 45 degrees.
Step-by-step explanation:
The sum of the three angles in a triangle is always 180 degrees. Since we know two angles, 45 and 90 degrees, we can find the measure of the third angle by subtracting the sum of these two angles from 180 degrees.
The measure of the third angle = 180 - (45 + 90) = 180 - 135 = 45 degrees.
Therefore, the measure of the third angle is 45 degrees.
Learn more about Triangle angles