The length of a side of an equilateral triangle is x - 4.5. First express its perimeter as a sum. Next express its perimeter as a product. Explain why the two expressions are equivalent.

Equilateral triangle means all sides have equal length.

Perimeter

As a sum: (x-4.5) + (x-4.5) + (x-4.5)

As a product: 3 * (x-4.5)

They are equivalent because 3 times a number is just the sum of three of the number.