Use the Triangle Angle Sum Theorem to find the measure of the third angle if the first and second angle measure 63° and 40° .(1 point)
According to the Triangle Angle Sum Theorem, the sum of the three angles in a triangle is always 180°.
So, let's call the measure of the third angle x°.
Now we can set up the equation:
63° + 40° + x° = 180°
Combining like terms, we have:
103° + x° = 180°
Subtracting 103° from both sides, we get:
x° = 180° - 103°
x° = 77°
Therefore, the measure of the third angle is 77°.