Answer: 144 units
Explanation:
CD = 3x + 8 units
DB = 4x + 10 units
BC = 8x units
From the figure, we know that BC = CD + DB. Now we have to substitute values of each segment and then find the value of x. Once we find x, then substitute in 8x to find the measure of BC.
Therefore,
CD + DB = BC
3x + 8 + 4x + 10 = 8x
7x + 8 + 10 = 8x
7x + 18 = 8x
18 = 8x - 7x
1x = 18
=> x = 18
Hence, BC = 8x = 8(18) = 144 units