Answer:
a=36, b=18, c=39
Explanation:
a + b + c = 93
You are told side a is is twice as long as b so a=2b. Plug that into your equation.
2b + b + c = 93
simplified gives you 3b + c = 93
Now you know c is 3 feet longer than a. You already know a is equal to 2b. So c is equal to 2b + 3. Plug that into your equation.
3b + (2b + 3) = 93
Simplified it is now 5b + 3 = 93.
Subtract 3 from both sides of the equal sign to get
5b = 90
Divide both sides by 5.
b = 18
Now you know side a is twice as long as b so side a must be 36.
a = 36
You also know side c is 3 feet longer than side a so side c must be 39
c = 39
Test your answers by adding all 3. 18 + 36 + 39 = 93