Question

the sum of three numbers is 123. the second number is 9 less than two times the first number. the third number is 6 more than three times the first number. find the three number

Answer 1

Let the first number be x. The second number is 2x−9, and the third number is 3x+6.
x + 2x−9 + 3x+6 = 123
Collect like terms:
6x − 3 = 123
Solve:
6x = 126
x = 21
Plug the x-value back in:
(2 x 21) − 9 = 33
(3 x 21) + 6 = 69

The three numbers are 21, 33, and 69.