SOLUTION: One number is 12 more than another. The sum of the smaller number and twice the larger number is 39. Find the larger number

Algebra ->  Graphs -> SOLUTION: One number is 12 more than another. The sum of the smaller number and twice the larger number is 39. Find the larger number      Log On


   



Question 126022: One number is 12 more than another. The sum of the smaller number and twice the larger number is 39. Find the larger number
Found 2 solutions by marcsam823, josmiceli:
Answer by marcsam823(57) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = the smaller number
Let x + 12 = the larger number
The sum of the smaller number (x) and two times the larger number [2(x + 12)] is:
Set up equation:
x + 2(x + 12) = 39
Solve:
x + 2x + 24 = 39
3x = 15
x = 5 = smaller number
x + 12 = 17 = larger number
Substitute and check:
5 + 2(17) = 5 + 34 = 39

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Call the numbers a and b
b+=+a+%2B+12
a+%2B+2b+=+39
---------------
a+-+b+=+-12
a+%2B+2b+=+39
Multiply the 1st equation by -1 and add them
-a+%2B+b+=+12
a+%2B+2b+=+39
----------------
3b+=+51
b+=+17 answer