Solve the given simultaneous equations in x^2, x and y

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The simultaneous equations were solved by first manipulating the equations to find a relationship between x and y. The derived quadratic equation was x^2 + 6x - 40 = 0, yielding solutions x = 4 and x = -10. For x = 4, the corresponding value of y is -2/3, while for x = -10, y is -23/24. The discussion also notes a potential error in the original post regarding the omission of 'x' in some instances. Overall, the approach appears thorough, with no quicker methods identified.
chwala
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Homework Statement
See attached
Relevant Equations
Simultaneous equations
1693395998519.png
In my approach i have,

##\dfrac{x^2}{4} -1 = \dfrac{1}{y+1}##

##9-\dfrac{3}{2}=\dfrac{1}{y+1}##

then,

##\dfrac{x^2}{4} -1= 9-\dfrac{3}{2}##

##x^2-4=36-6x##

##x^2+6x-40=0##

##x_1=4, x_2=-10##

it follows that when ##x=4## then ##y+1=\dfrac{1}{3}## ⇒##y=-\dfrac{2}{3}##

and when ##x=-10## then ##y+1=\dfrac{1}{24}## ⇒##y=-\dfrac{23}{24}##

Seeking alternative ways...
 
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I see no reason to hope there is a quicker way. Btw, you seem to have dropped 'x' in a couple of places when typing your post.
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks

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