Question

Points A, B and C are collinear. Point B is between A and C. Find x if AC=20, BC=x-19 and AB=x+17.

Answer 1

11

Explanation:

20-[(x-19)+(x+17)]

=20-2x+2

=22-2x

As AB+BC=AC, 22-2x=0.

Thus 2x=22

x=11

it should be right