SOLUTION: Find values for m and b in the following system so that the solution to the system is (-3, 4). 5x+7y=b mx+y=22

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Question 74726: Find values for m and b in the following system so that the solution to the system is (-3, 4).
5x+7y=b
mx+y=22
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
5x%2B7y=bPlug in (-3,4) into the first equation
5%28-3%29%2B7%284%29=bSolve for b
-15%2B28=b
b=13
Now plug in (-3,4) into the 2nd equation
m%28-3%29%2B%284%29=22
-3m%2B4=22
-3m=18
m=-6
So m=-6. Use this info to complete the system of equations
5x%2B7y=13
-6x%2By=22


Check:
5x%2B7y=13if we plug in (-3,4) it should satisfy the sytem
-6x%2By=22
5%28-3%29%2B7%284%29=13
-6%28-3%29%2B%284%29=22
-15%2B28=13
18%2B4=22
13=13works
22=22works