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2 years ago

2x+6y=7 3x+9y=1 eliminacion

Mathematics

1 answer:

cupoosta [38]2 years ago

3 0

Answer:

x=1/3 y=19/18

Step-by-step explanation:

you want to use elimination so you need the x or ys to have the same value, in this case x is easier to make do that so we choose to eliminate x by multiplying the equations to get the same coefficient in front of both xs.

3(2x+6y=7)

6x+36y=21

<u>- (6x+18y=2)</u> then subtract to be left with just ys and you get

18y=19 next divide by 18

y=19/18 plug in for y to one of the original equations (I did the first one) in order to solve for x

2x+6(19/18)=7 simplify (6 and 18 reduced so that it is 19/3)

2x+19/3=7 -19/3 on both sides

2x=7-19/3 make a common denominator

2x=21/3 -19/3 simplify like terms

2x=2/3 divide by 2 which is the same as multiplying by 1/2

x=(2/3)(1/2) then the 2s cancel and you get

x=1/3

Hope this helps! :)

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