Question

Points A, B, and C are collinear. Point B is between A and C. Find the length indicated. AB= 5x-15, BC=3x-5, and AC=28. Find AB

Answer 1

Answer: AB is 15

Step-by-step explanation: First, you need to draw a picture and label the parts of the line: AB=5x-15; BC= 3x-5; AC =28. Because of the segment addition postulate, you set the equation to be 5x-15+3x-5=28. Then you solve:

5x-15+3x-5=28

Add like terms:

8x-20=28

Add 20 to both sides

8x=48

Divide by 8

x=6

Now, you need to find the measure of AB, so you plug the 6 into the x variable for 5x-15

5(6)-15

30-15

AB=15