Explanation:
<CDB = 1 + 6x
<DCB = 58°
<CBF = 11x + 9
Now
<CBF = < CDB + < DCB ( Exterior angle of a triangle is equal to the sum of two opposite interior angles )
11x + 9° = 58° + 1° + 6x
11x - 6x = 59° - 9°
5x = 50°
x = 10°
<C = 58°
<D = 1 + 6 * 10° = 61°
< B = 11 * 10° + 9 ° = 110° + 9 = 119°
Hope it will help :)❤