Answer:
m<C = 56°
m<D = 124°
Explanation:
Of CDEF is a parallelogram then the sum of angle m<C and angle m<D must be equal to 180°
4x + 28 + 17x + 5 = 180 add like terms
21x + 33 = 180 subtract 33 from both sides
21x = 147 divide both sides by 21
x = 7 now to find the measure of each angle replace x with 7