The perimeter of a triangle

Question

The perimeter of a triangle is 80 centimeters. If two sides are equally long and the third side is 8 centimeters longer than the other, find the lengths of the three sides. What is the length of each of the two equally long side? And what is the length of the longer side?

Answer 1

You have a triangle with two equal sides a Perimeter of 80 cm with the third side 8 cm longer than the other side.

P =s₁ + s₂ + s₃

Let s₁ = s₂ = s for the measure each of the two equal sides

Let s₃ = s + 8 for the third side

80 = s + s + s + 8

80 = 3s + 8

Subtract 8 from both sides to isolate the variable

80 - 8 = 3s

72 = 3s

Divide both sides by 3 to solve for s

24 = s

s₁ = 24

s₂ = 24

s₃ = 24 + 8 = 32