Question

Find the perimeter of the triangle

Answer 1

Explanation:

P = a + b + c

Solve and algebraic equation

x + 12 + 2x + 5 + 3x - 2 = P

Combine like terms

6x + 15

(x + 2x + 3x) (12 + 5 -2)

P = 6x + 15

Answer 2

57 units

Explanation:

You want to know the perimeter of an equilateral triangle with sides marked (x+12), (2x+5), and (3x-2).

Value of x

Since the sides are marked as the same length, we can equate the expressions for the side lengths:

2x +5 = x +12

x = 7 . . . . . . . . subtract x+5

Perimeter

Then the length of each side of the triangle is ...

x +12 = 7 +12 = 19

The perimeter of the equilateral triangle is 3·19 = 57 units.