Answer:
Equation: 3(x+5)=60
Solution: 15 inches
Step-by-step explanation:
Let x represent the original side length of the equilateral triangle. Then, the new length of each side is x+5. Because a triangle has three sides, the new perimeter is 3(x+5), which is 60 inches. Dividing both sides by 3, we get that x+5=20, so x=15.
