Solving Equations: 2 Equations, 1 Unknown Variable

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To solve the system of equations y(x² + 4) = 5 and x² + y² - 2y = 0, start by isolating y in the first equation, yielding y = 5/(x² + 4). The second equation can be rearranged to form a quadratic in y: y² - 2y = -x². This quadratic can be solved using the quadratic formula, allowing for substitution back into the first equation. By substituting y from the first equation into the second, a manageable equation can be formed for solving x.
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I am given 2 equations (for a calculus problem)...
y(x2 +4)=5 and x2 +y2 -2y=0.
I know how to solve for y in terms of x for the first equation, but I am seriously stumped on how to get passed:
y2 -2y=-x2
 
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We do not see yet how the calculus aspects will be involved, but only your two equations which you wish to solve. The first equation will permit you to find y in terms of x. The second equation will allow you to find x2 in terms of y. One of these will allow you to perform a substitution which will yield an equation more easily managed and solved.

note that you seem to almost have the right idea with your line at the botton of your post. When you rectify that, you will have something to substitute.
 
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solving for y in the second equation is not difficult. Ever solved quadratic equations? do you know any formula to solve a quadratic in y?? (x is constant)

or... add one to both sides.. do u see anything familiar?
 
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