Two of the angles in a triangle measure 55° and 35°. What is the measure of the third angle?

90 degrees

Step-by-step explanation:

55+35=90

180-90=90

90 degrees

Step-by-step explanation:

The sum of the angles of a triangle are 180

55 + 35 + x = 180

90 + x = 180

Subtract 90 from each side

90+x-90 = 180-90

x = 90

The third angle is 90 degrees