The perimeter of a triangle is 84. The longest side is 7 meters less than twice the length of the shortest side, x. The middle side is 7 meters longer than the shortest side. What is the length of each side?



Answer :

Perimeter = Side + Side + Side
Side 1 = x
Side 2 = x + 7
Side 3 = 2x-7

Plug into the equation:
84 = x + (x + 7) + (2x-7)
84 = x + x + 7 + 2x - 7

Combine like terms:
84 = 4x

Divide by 4 and solve for x:
21 = x

Side 1 = 21

Side 2 = 28
21+7=28

Side 3 = 35
21(2) - 7 = 42 - 7 = 35