Question 215480
Solve by using the elimination method

{{{7x+6y=11}}}  Equation A
{{{7x-6y=-25}}}  Equation B


Step 1.  Subtract Equation B from Equation A

{{{7x-7x+6y-(-6y)=11-(-25)}}}


{{{12y=36}}}


{{{12y/12=36/12}}}


{{{y=3}}}


Step 2.  Now add Equation A and B.


{{{7x+7x+6y-6y=11-25}}}


{{{14x=-14}}}


{{{14x/14=-14/14}}}


{{{x=-1}}}


Step 3. We can check if x=-1 and y=3 satisfies Equations A and B


{{{7x+6y=7*(-1)+6*3=-7+18=11}}}  Equation A and is a true statement.


{{{7x-6y=7*(-1)-6*3=-7-18=-25}}}  Equation B and is a true statement.


Step 4.  ANSWER:  The solution is (-1,3) or x=-1 and y=3.


I hope the above steps were helpful.


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Good luck in your studies!


Respectfully,
Dr J