Answer: The dimensions of the flower bed are,
39 ft, 57 ft and 78 ft.
Step-by-step explanation: Of the three sides, one side is twice the length of the shortest. Let the shortest side be labelled as b. That means one of the sides of the flower bed measures twice b, that is, 2b.
Also we are told that the third side measures 18 feet more than the shortest side, b. The third side can now be represented by b + 18.
So the triangle has sides
b, 2b and b + 18
If the perimeter is 174, then
b + 2b + (b + 18) = 174
b + 2b + b + 18 = 174
4b + 18 = 174
Subtract 18 from both sides of the equation
4b = 156
Divide both sides of the equation by 4
b = 39.
Therefore the shortest side of the triangle measures 39 ft while the other two sides measure 78 ft (twice the length of b) and 57 ft (18 ft more than the shortest side)