SOLUTION: Hello. I'm trying to solve this System of Equations with three variables. r+s=5 3s+2t=-1 4r+t=14

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Question 726685: Hello.
I'm trying to solve this System of Equations with three variables.
r+s=5
3s+2t=-1
4r+t=14
Found 2 solutions by lwsshak3, tanjo3:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
(1) r+s=5
(2) 3s+2t=-1
(3) 4r+t=14
..
3s+3r=15 (mult.1st eq by 3)
3s+2t=-1
subtract
3r-2t=16
8r+2t=28 (mult.3rd eq by 2)
add
11r=44
r=4
s=5-r=1
t=14-4r (3rd eq)
=14-16
=-2
r=4
s=1
t=-2

Answer by tanjo3(60) About Me  (Show Source):
You can put this solution on YOUR website!
Equation 1: r+%2B+s+=+5
Equation 2: 3s+%2B+2t+=+-1
Equation 3: 4r+%2B+t+=+14
Solve for s in (1):
s+=+5+-+r
Solve for t in (2):
3%285+-+r%29+%2B+2t+=+-1
15+-+3r+%2B+2t+=+-1
2t+=+3r+-+16
t+=+%283r+-+16%29%2F2
Solve for r in (3):
4r+%2B+%283r+-+16%29%2F2+=+14
4r+%2B+%283%2F2%29r+-+8+=+14
%2811%2F2%29r+=+22
%2811%2F2%29r+=+22
r+=+4
Sub r=4 in (1)
4+%2B+s+=+5
s+=+1
Sub s=1 in (2)
3%281%29+%2B+2t+=+-1
2t+=+-4
t+=+-2
So, r=4, s=1, t=-2