Question

AB = 2x + 20, AC = x + 20, and BC = 8.
Find AB.

Points A, B, C are collinear. Point B is between A and C. Find the length indicated.

Answer 1

AB= 2x+20 cm
BC= 8 cm
AC= x+20 cm

AC= AB + BC
x + 20 = 2x + 20 + 8
2x - x = 20 - 20 - 8
x = -8

AB= 4 cm
BC= 8 cm
AC= 12 cm