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Solving Linear Systems: Using Substitution
x=3y-4
3y - 4x = 6
someone pls help

1 Answer

3 votes

Answer:

x = -2/3

y = 10/9

Explanation:

3y - 4x = 6

x=3y-4

Substitute the second equation into the first for x

3y - 4( 3y-4) =6

3y - 12y +16 = 6

Combine like terms

-9y +16 = 6

Subtract 16 from each side

-9y +16-16 = 6-16

-9y = -10

Divide by -9

-9y/-9 = -10/-9

y = 10/9

x = 3y -4

x =3(10/9) -4

=10/3 - 12/3

=-2/3

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