Question

Solve this system using elimination (20 POINTS)
4x-7y=3
x-7y=-15

Answer 1

x = 6, y =3

Explanation:

4x-7y=3

x-7y=-15

Multiply the first equation by -1

-4x+7y=-3

Then add this to the second equation to eliminate y

-4x+7y=-3

x-7y=-15

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-3x +0y = -18

-3x = -18

Divide by -3

-3x/-3 = -18/-3

x = 6

Now find y

x -7y = -15

6 -7y = -15

Subtract 6 from each side

6-7y-6 = -15-6

-7y = -21

Divide by -7

-7y/-7 = -21/-7

y =3