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3 votes
Solve.
X = -7
4x - 4y = 12
Submit

User DonPablo
by
8.5k points

2 Answers

9 votes

Answer:

Point Form:

( − 7 , − 10 )

Equation Form:

x = − 7, y = − 10

Explanation:

Solve for the first variable in one of the equations, then substitute the result into the other equation.

User SixFingers
by
8.0k points
1 vote

Answer:

y = -10

Explanation:

4x - 4y = 12

Substitute the x with -7, since it has been given.

4(-7) - 4y = 12

-28 - 4y = 12

Add 28 onto both sides

-28 + 28 - 4y = 12 + 28

-4y = 40

Divide by -4 to isolate the variable

-4y/-4 = 40/-4

y = - 10

Check:

Substitute the y and x

4x - 4y = 12

4(-7) - 4 ( -10 ) = 12

-28 + 40 = 12

12 = 12

or.....

try to see if x stays as -7

4x - 4y = 12

4x - 4 (-10) = 12

4x + 40 = 12

Subtract 40 onto both sides

4x + 40 - 40 = 12 - 40

4x = -28

Divide by 4 onto both sides to isolate the variable

4x/4 = -28/4

x = -7

And it's correct

Hope this helped!

User Thibaut
by
9.2k points

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