SOLUTION: how do you solve this by elimination? x+y=2 2x-y=-5

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Question 228486: how do you solve this by elimination?
x+y=2
2x-y=-5
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
How do you solve this by elimination?

x%2By=2 Equation A
2x-y=-5 Equation B

Step 1. Add Equations A and B

x%2B2x%2By-y=2%2B%28-5%29

3x=-3

Step 2. Divide by 3 to both sides of the equation

3x%2F3=-3%2F3

x=-1

Step 3. Now substitute x=-1 to either Equations A and B to find y. Let's substitute into Equation A.

x%2By=2

-1%2By=2

Step 4. Add 1 to both sides of the equation

-1%2By=1=2%2B1

y=3

Step 5. As a check see if x=-1 and y=3 satisfies Equation B 2x-y=-5

2%2A%28-1%29-3=-5

-5=-5 which is a true statement and so x=-1 and y=3 satisfies both Equations A and B.

Step 6. ANSWER: The solution is x=-1 and y=3. This is the intersection point (-1,3) between the two lines.

Here's a graph of the two equations and note the intersection point at (-1,3)

graph%28400%2C+400%2C+-10%2C10%2C+-10%2C+10%2C+-x%2B2%2C+2x%2B5%29

I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J