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3 years ago

7x-y=19 2x-3y=19 solve by elimination

Mathematics

1 answer:

avanturin [10]3 years ago

8 0

Answer:

x=2 y=-5

Step-by-step explanation:

7x-y=19

2x-3y=19

Multiply the first equation by -3

-3(7x-y)=19*-3

-21x +3y =-57

Add this to the second equation to eliminate y

-21x +3y =-57

2x-3y=19

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

-19x = -38

Divide by -19

-19x/-19 = -38/-19

x = 2

Now we need to find y

7x-y = 19

7(2) -y =19

14 -y =19

Subtract 14 from each side

14-14 -y=19-14

-y=5

Multiply by -1

y = -5

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