SOLUTION: Solve by method of elimination: 2x +3y =10 -3x+y =18

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Question 225957: Solve by method of elimination: 2x +3y =10
-3x+y =18
Answer by drj(1380) About Me  (Show Source):
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Solve by method of elimination:

2x +3y =10 Equation A
-3x+y =18 Equation B

Step 1. Multiply Equation B by 3 and subtract from Equation A to eliminate y terms

%282x%2B3y%29-%28-9x%2B3y%29=10-3%2A18

2x%2B9x%2B3y-3y=-44

11x=-44

Step 2. Divide by 11 to both sides of the equation

11x%2F11=-44%2F11

x=-4

Step 3. Substitute x=-4in Equation A 2x+%2B3y+=10 to find y

2%2A%28-4%29%2B3y=10

-8%2B3y=10

Step 4. Add 8 to both sides of the equation to find y

-8%2B3y%2B8=10%2B8

3y=18

Step 5. Divide by 3 to both sides of the equation

3y%2F3=18%2F3

y=6

Step 6. Check solution of x=-4 and y=6 with Equation B -3x%2By+=18

-3%2A%28-4%29%2B6=18

12%2B6=18

18=18 which is a true statement.

Step 7. ANSWER: The solution is (-4,6) or x=-4 and y=6 for the linear system of equations.

I hope the above steps and explanation were helpful.

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Respectfully,
Dr J
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