SOLUTION: Examples on how to solve 2 variables in linear equation

Question 471468: Examples on how to solve 2 variables in linear equation

Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
3 x -7 y = 15 .............1
-5 x + 4 y = -25 .............2

multiply (1)by 4
Multiply (2) by 7
12 x -28 y = 60
-35 x + 28 y = -175
Add the two equations
-23 x = -115
/ -23
x = 5
plug value of x in (1)
3 x -7 y = 15
15 -7 y = 15
-7 y = 15-15
-7 y = 0
y = 0
(5,0) is the solution
...
2 x -3 y = 12 .............1
4 x + 1 y = 10 .............2

multiply (1)by 1
Multiply (2) by 3
2 x -3 y = 12
12 x + 3 y = 30
Add the two equations
14 x = 42
/ 14
x = 3
plug value of x in (1)
2 x -3 y = 12
6 -3 y = 12
-3 y = 12 -6
-3 y = 6
y = -2

(3-2)is the solution
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