Answer:
Step-by-step explanation:
If B is the midpoint of AC, then AB = BC and AB+BC = AC
AB +AB = AC
2AB = AC
2(2x+12) = 10x-12
4x+24 = 10x-12
collect like terms:
4x-10x = -12-24
-6x = -36
x = -36/-6
x = 6
Get AB:
AB = 2x+12
AB = 2(6)+12
AB = 12+12
AB = 24
Since AB = BC, hence BC = 24
AC = AB+BC
AC = 24+24
AC = 48
