SOLUTION: PROBLEM: the sum of two numbers is 10. three times the larger decreased by twice the smaller is 15. find the numbers. i tried to plug in the numbers to a formula and i get stuck

Algebra ->  Problems-with-consecutive-odd-even-integers -> SOLUTION: PROBLEM: the sum of two numbers is 10. three times the larger decreased by twice the smaller is 15. find the numbers. i tried to plug in the numbers to a formula and i get stuck      Log On


   

Question 718820: PROBLEM: the sum of two numbers is 10. three times the larger decreased by twice the smaller is 15. find the numbers.
i tried to plug in the numbers to a formula and i get stuck.
i did:
m+n=10
3m-2n=15 and then i combined them and got 4m-n=25 but it doesn't make sense
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +m+%2B+n+=+10+
(2) +3m+-+2n+=+15+
-------------------
(1) +n+=+10+-+m+
Substitute this result into (2)
(2) +3m+-+2%2A%28+10+-+m+%29+=+15+
(2) +3m+-+20+%2B+2m+=+15+
(2) +5m+-+20+=+15+
(2) +5m+=+35+
(2) +m+=+7+
and, since
(1) +m+%2B+n+=+10+
(1) +7+%2B+n+=+10+
(1) +n+=+3+
-------------
check:
3 times the larger is 21
twice the smaller is 6
+21+-+6+=+15+
OK