The perimeter of a triangle is 79.75 inches. The second side of the triangle is half as big as the first side. The third side is 7.25 inches larger than the first side. What is the length of the longest side of the triangle? make the answer in decimals.

Let the second side be x inches long, Then:-

first side = 2x and third side = 2x + 7.25 inches long.

therefore: - x + 2x + 2x + 7.25 = 79.75

5x = 79.75 - 7.25 = 72.50

x = 72.50 / 5

= 14.5 ins

So longest side = 2x + 7.25

= 14.5 * 2 + 7.25

= 36.25 inches (answer).