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If 2x-1y=7 ,1x-2y=2then what is the solution of x and y

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Answer:

x = 4, y = 1

Explanation:

To do these:

  • Solve one of the equations for one of the variables.
  • Substitute that expression into the other equation.
  • Find what that variable equals. It'll be a number.
  • Put that number into either equation to find the other variable.

It doesn't matter which equation or variable you choose, but looking at those two equations, the second one is a little easier to solve for x:

x - 2y = 2 becomes: x = 2y + 2

We then take this expression for x and plug it into the other equation where x is. So the other equation is:

2x - y = 7

And if I put in that expression for x it becomes:

2(2y + 2) - y = 7

Dd you understand that step? Because it's super-important. Where x was, I simply put what we found that x was the same as from the other equation.

And now look: there are only y terms, so we can solve for y:

4y + 4 - y = 7

3y = 3

y = 1

Now that we know what y is, we just put it into either equation and solve for x. It's a bit easier to use this equation:

2x - y = 7 Substitute y = 1 to get:

2x - 1 = 7

2x = 8

x = 4

You can check that answer is correct by plugging (1,4) into the other equation:

x - 2y = 2

4 - 2(1) = 2

4 - 2 = 2

2 = 2 So the answer works there too.

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