SOLUTION: 3x-y=7, y=4x-11

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Question 228648: 3x-y=7, y=4x-11
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
3x-y=7 Equation A
y=4x-11 or -4x+y=-11 Equation B

Step 1. Add Equations A and B to eliminate the y-variable.

3x-4x-y%2By=7-11

-x=-4 or x=4 after multiplying by -1 to both sides of the equation.

Step 2. Substitute x=4, into equation A 3x-y=7

3%2A%284%29-y=7

Add y-7 to both sides of the equation

12-y%2By-7=-7%2By-7

5=y

Check if x=4 and y=5 satisfies Equation B -4x%2By=-11

-4%2A%284%29%2B5=-16%2B5=-11 which it does.

Step 3. The solution is x=4 and y=-11.

I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J