Abc is a straight line. The length of AB is four times bigger than BC.

AC=75

AB=15 BC=60

Step by step:

AB+BC=AC

AC=75

Plug in AC to the equation: AB+BC=75

BC=4 (ab)

Plug in BC into the equation: AB+4 (AB) = 75

Simplify: 5AB=75

Divide each side by 5: AB=15

BC=4 (15) = 60

Answer: AB = 60, BC = 15

Step-by-step explanation:

AB is 4 times bigger than BC ⇒ AB = 4BC

Use the Segment Addition Property: AB + BC = AC

and substitution (replace AB with 4BC) and (AC with 75) to solve for BC

4BC + BC = 75

5BC = 75

BC = 15

AB = 4BC

= 4 (15)

= 60