SOLUTION: x-2y=3 5x+4y=8

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Question 229941: x-2y=3
5x+4y=8
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
x-2y=3 Equation A
5x%2B4y=8 Equation B

Step 1. Multiply Equation A by 2 to both sides of the equation

2x-4y=6 Equation A1
5x%2B4y=8 Equation B

Step 2. Add Equations A1 and B to get rid of the y-terms

2x%2B5x-cross%284y%29%2Bcross%284y%29=6%2B8

7x=14

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

cross%287%29x%2Fcross%287%29=14%2F7

x=2

Step 4. Substitute x=2 into Equation A x-2y=3 to get y

2-2y=3

Add 2y-3 to both sides of the equation

2-cross%282y%29%2Bcross%282y%29-3=cross%283%29%2B2y-cross%283%29

-1=2y

Divide by 2 to both sides of the equation

-1%2F2=cross%282%29y%2Fcross%282%29

y=-1

Check solution x=2 and y=-1%2F2 into Equation B 5x%2B4y=8

5%2A2%2B4%2A%28-1%2F2%29=8

10-2=8

8=8 which is a true statement.

Step 5. ANSWER: The solution is x=2 and y=-1%2F2 or (2, -1/2) our intersection point.

I hope the above steps were helpful.

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And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV