A garden is the shape of an isosceles triangle. It has a perimeter of 25 ft. The length of the shortest side of the triangle is 2 ft less than the length of one of the longer sides.
Which term completes the equation to find the length of the shorter side?
A
B
C
D
Let x be the length of one of the longer sides of the triangle.
The length of the shortest side is x - 2.
The perimeter of the triangle is the sum of all three sides, so we have x + x + (x - 2) = 25.
Combining like terms, 3x - 2 = 25.
Adding 2 to both sides, 3x = 27.
Dividing both sides by 3, x = 9.
The length of the shortest side is x - 2 = 9 - 2 = 7.
The term that completes the equation to find the length of the shorter side is C.