Question

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.

Answer 1

The sides of an equilateral triangle are same. So if one of the sides is (x-4.5), all the sides are (x-4.5).

Let the sides are a=(x-4.5), b=(x-4.5), c=(x-4.5)

1. Perimeter(as sum) = a+b+c

= (x-4.5)+(x-4.5)+(x-4.5)

= x+x+x-4.5-4.5-4.5

= 3x - 13.5

2. Perimeter (as product) = 3×a

= 3×(x-4.5)

= 3×x - 3×4.5

= 3x - 13.5

(you can write 3×b or 3×c also as a=b=c.)

Both perimeter as sum and perimeter as product are same as adding a number three times is the same as multiplying it by 3.

Explanation: