Question

An equilateral triangle has

sides of 4x + 10. Write an
expression for the perimeter of
the triangle.

Determine the value of x when the perimeter is 42.

Answer 1

x = 1 if the perimeter is 42

Explanation:

Given

s = 4x + 10

when Perimeter = 42, what is x?

Solution

Perimeter = 3s

Perimeter = 3(4x +10) Remove the brackets

Perimeter = 12x + 30

Let the Perimeter = 42

42 = 12x + 30 Subtract 30 from both sides

42-30 = 12x + 30-30 Combine

12 = 12x Divide by 12

12/12 = 12x/12

x = 1