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Solving Simultaneous Equation By Elimination Method

Solving Simultaneous Equation By Elimination 

Method

3x+2y=6

 5y= 8

In order to solve by elimination, coefficients of one of the variables must be the same in both equations so that the variable will cancel out when one equation is subtracted from the other

3x+2y=65xy=8


5×3x+5×2y=5×6,3×5x+3(1)y=3×8

Simplify

15x+10y=30,15x3y=24

Subtract 15x3y=24 from  by subtracting like terms on each side of the equal sign

15x15x+10y+3y=3024

Cancel out 15x - 15x to get 

10y+3y=3024

Add  to  

13y=3024

Subtract 24 from 30 to get

13y= 6

Divide both side by 13

y=136

5x136=8

5x=13110

Divide through by 5

x=1322

x=1322,y=136

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