One number is 9 more than twice another number. If the sum of the numbers is 129, find both numbers.

40 and 89

Step-by-step explanation:

let x be the number then the other number is 2x + 9, then

x + 2x + 9 = 129, that is

3x + 9 = 129 ( subtract 9 from both sides )

3x = 120 ( divide both sides by 3 )

x = 40

Thus the numbers are

x = 40 and 2x + 9 = 2(40) + 9 = 80 + 9 = 89

step-by-step explanation:

just plug in each number for x and see which ones work and don't