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
