Isolating y in Equation: y^2 + 2y = -2x +2

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To isolate y in the equation y^2 + 2y = -2x + 2, one can recognize it as a quadratic equation. Applying the quadratic formula yields the solutions y = -1 ± √(3 - 2x). The discussion highlights the initial confusion about the correct form of the solution, which is clarified through the application of the quadratic formula. The user confirms that using this method resolves their issue. Understanding the quadratic nature of the equation is key to finding the correct solutions.
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Homework Statement


I realize this is probably a very simple question but I just can't seem to figure it out. I need to isolate the following equation for y.

y^2 + 2y = -2x +2

The Attempt at a Solution


In my solutions it says that the answer after you isolate for y you should get

y = -1 + \sqrt{3-2x}

Im not sure how they got that though.
 
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I assume you mean that the answer is y=-1 \pm \sqrt{3-2x}?

Your equation is quadratic in y, so I would use the quadratic equation.:wink:
 
Oh I totally missed that. I tried it out and it works. Thanks a lot!
 

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