(x2+y2–1)3-x2y3=0
The teacher will be very surprised to see your correct solution 😉
The solution set is obviously symmetric with respect to the $y$-axis. Therefore we may assume $x\geq 0$. In the domain $\{(x,y)\in {\mathbb R}^2\ |\ x\geq0\}$ the equation is equivalent with\n$$x^2+ y^2 -1=x^{2/3} y\ ,$$\nwhich can easily be solved for $y$:\n$$y={1\over2}\bigl(x^{2/3}\pm\sqrt{x^{4/3}+4(1-x^2)}\bigr)\ .$$\nNow plot this, taking both branches of the square root into account. You might have to numerically solve the equation $x^{4/3}+4(1-x^2)=0$ in order to get the exact $x$-interval.
(x2 + y2 - 1)*3 - x2*y3 = 0
(x2+y2-1)*3-x2*y3 = 0
x2*3+y2*3-1*3-x2*y3 = 0
-3 + 3*x2 + 3*y2 - x2*y3 = 0
y3 = 3 - 3*x2 / ((3*y2 - x2*y3)/y3)
3*(-1 + x2 + y2)
y3_1 = ----------------
x2
sum
3*(-1 + x2 + y2)
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x2
=
3*(-1 + x2 + y2)
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x2
product
3*(-1 + x2 + y2)
----------------
x2
=
3*(-1 + x2 + y2)
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x2