Given line l is a perpendicular bisector of ⎯⎯⎯⎯⎯⎯⎯⎯CB¯ and AB = x + 7.5 and AC = 3x - 10.9 find x. (Round to the nearest tenth)

If line l is a perpendicular bisector of by the converse of the perpendicular bisector theorem.
Then,
AB = AC
Replacing
x+7.5 =3x-10.9
Solve for x
7.5+10.9 = -x+3x
18.4 = 2x
Change sides
2x = 18.4
x= 18.4/2
x = 9.2
Hence, the correct answer is x=9.2