SOLUTION: one number is 18 more than 3 times another number. the difference in the numbers is 54. find the numbers

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Question 950570: one number is 18 more than 3 times another number. the difference in the numbers is 54. find the numbers
Answer by aYummyNoodle(10) About Me  (Show Source):
You can put this solution on YOUR website!
let x = the first number
let y = the second number
We can now turn the word problem into two equations with x and y being the two numbers:
x=3y%2B18 and
x-y=54
Of course, there are 3 ways to solve a system of linear equations: graphing, substitution, and elimination. For this system, I will use substitution.
The first equation already has x isolated so we can just plug the value in to the second equation:
%283y%2B18%29-y=54
2y%2B18=54
2y=36
y=18
So the smaller number is 18.
Now we can plug the y value back in to the original second equation:
x-18=54
x=72
So the larger number is 72.
The two numbers are 18 and 72.