Answer:
Explanation:
ABD = ABC + DBC
Eqivalent to:
78 = (5x + 3) + (5x - 5)
78 = 5x + 5x + 3 - 5
78 = 10x - 2
80 = 10x (move -2 to the left side and get 78 + 2 = 80)
8 = x (80/10 = 8)
With x = 8,
ABC = 5x - 5 = 8*5 - 5 = 40 - 5 = 35
DBC = 5x +3 = 8*5 + 3 = 40 + 3 = 43