SOLUTION: simultaneous equations x-5/3y=7 4/7x+y=-13/7

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Question 170370: simultaneous equations
x-5/3y=7
4/7x+y=-13/7
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
x-5y/3=7
4x/7+y=-13/7 multiply this equation by 5/3 & add
(5/3)(4x/7)+5y/3=-(5/3)(13/7)
20x/21+5y/3=-65/21
x-5y/3=7
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20x/21+21x/21=7-65/21
41x/21=(7*21-65)/21
41x/21=(147-65)/21
41x/21=82/21
41x=82
x=82/41
x=2 ans.
2-5y/3=7
-5y/3=7-2
-5y/3=5
-5y=5*3
-5y=15
y=15/-5
y=-3 ans.
Proof:
4*2/7-3=-13/7
8/7-21/7=-13/7
-13/7=-13/7