Quadrilateral ABCD is inscribed in circle O.
What is m∠C ?
I agree with CPhill
B + D = 180 ....so...
[ 2x + 3 ] + [ 4x + 3 ] = 180
6x + 6 = 180
6x = 174 divide both sides by 6
x = 29
So
C = 2(29) + 1 = 59°
+121 
