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Solve the following system of linear equations using elimination. x+4y= -9 -2x + 3y= -4

User Knagaev
by
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1 Answer

5 votes

(-1, -2)

1) Let's solve that system, by the Elimination Method.

Let's eliminate the x terms on both, to begin with. Multiply the first equation by 2

x+4y= -9 x2

-2x + 3y= -4​

2x+8y= -18

-2x + 3y= -4​

-------------------------

11y= -22 divide both sides by 11

y= -2

2) Let's plug into any of those two equations, usually the simplest one, y=-2

x +4y = -9

x +4(-2) = -9

x -8 = -9

x =-9+8

x= -1

3) Testing it:

-2x + 3y= -4​

-2(-1) +3(-2) =-4

2 -6 = -4

-4 = -4 True!

Hence, the solution is (-1, -2)

User Lastmboy
by
6.8k points
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