help solve this problem

Question

BD bisects AC at point B. If AB = × + 3 and AC = 12. Solve for x and find the length of

Answer 1

Here is a possible sketch:

Notice that I noted segment AB ≅ segment BC. We can say that because B is the midpoint since BD bisects AC. That means that (x + 3) + (x + 3) = 12

(x + 3) + (x + 3) = 12

2x + 6 = 12

2x = 6

x = 3

If x = 3, then the length of AB or BC is 6 because they are "x + 3" long.