SOLUTION: Solve using the substitution method: r=-3s r+4s=10

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Question 376292: Solve using the substitution method:
r=-3s
r+4s=10
Found 2 solutions by user_dude2008, Fombitz:
Answer by user_dude2008(1862) About Me  (Show Source):
You can put this solution on YOUR website!
r+4s=10
-3s+4s=10
s=10
r=-3s=-3(10)=-30
Answers: r=-30, s=10

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.r=-3s
2.r%2B4s=10
Substitute eq. 1 into eq. 2 directly,
-3s%2B4s=10
highlight%28s=10%29
Then from eq. 1,
r=-3%2810%29
highlight%28r=-30%29