Answer: 9, 18 , 15
Explanation:
Set up algebraic expression
42 = x + 2x + (2x -3)
Solve for x
remove brackets and collect like terms
42= 5x - 3
Move constants to one side
5x = 42 + 3
5x = 45
Divide both sides by 5
X = 9
Sum back into equation to get the different numbers
9,18,15
Check that these add to 42
9 + 18 = 27 + 15 = 42