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If {4x-3y=17 and 2x-5y=-11 then y=?

User LMVogel
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1 Answer

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You need to solve this "system of linear equations." In other words, find a point (x,y) that satisfies both 4x-3y=17 and 2x-5y=-11.

Try solution by elimination. Multiply the 2nd equation by -2 to obtain -4x+5y=22. Add this result to the 1st equation. I'd suggest you write this out to see what is happening.

4x-3y=17

-4x+10y=22
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7y=39. Solving for y, we get y=39/7 (a rather awkward fraction).

Now find x. To do this, substitute 39/7 for y in either of the given equations. Solve the resulting equation for x.

Write your solution in the form (x, y): ( ? , 39/7).
User UIResponder
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