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Solve Each System by Elimination:-3x-5y=14-5x+7y=8

User JeanLaurent
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1 Answer

10 votes
10 votes

(-3, -1)

1) Solving this system by Elimination method:

Let's eliminate the x variables firstly:

-3x-5y=14 x -5 Multiply by the factor that yields the LCM (3,5) =15

-5x+7y=8 x 3 Multiply by the factor that yields the LCM (3,5) =15

15x +25y =-70

-15x +21y =24 Add both equations simultaneously

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46y= -46 Divide both sides by 46

y= -1

2) Plug y=-1, into the smaller coefficients equation, just for convenience

-3x -5y = 14

-3x -5(-1) = 14

-3x +5=14 Subtract 5 from both sides

-3x = 9

x= -3

3) So the answer to this Linear System is (-3, -1)

User Jeff Werner
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