Which two equations relate the measure of ∠4 to the measures of ∠1, ∠2, and/or ∠3. The measure of an angle 4 is the exterior angle of triangle it is formed by extending the base of the triangle. The triangle is with measures 1, 2, 3. The measure angle 4 is supplementary angle for measure angle 3.
A. m∠4 = m∠1 + m∠2
B. m∠4 = m∠2 + m∠3
C. m∠4 = 180° – (m∠1 + m∠2)
D. m∠4 = 180° – m∠3