AP Calculus AB Help!!! please help me on these two questions
1.For the curve given by 4x^2+y^2=48+2xy find the positive y-coordinate given that the x-coordinate is 2.

2.For the curve given by 4x^2+y^2=48+2xy show that there is a point P with x-coordinate 2 at which the line tangent to the curve at P is horizontal.

Question

AP Calculus AB Help!!! please help me on these two questions
1.For the curve given by 4x^2+y^2=48+2xy find the positive y-coordinate given that the x-coordinate is 2.

2.For the curve given by 4x^2+y^2=48+2xy show that there is a point P with x-coordinate 2 at which the line tangent to the curve at P is horizontal.

tkhunny · Answer

Have you considered substituting x = 2 and solving for y?

tmagloire1 · Answer

Is it that simple? I thought I might have to differentiate implicitly but i wasn't really sure where to start.

tmagloire1 · Answer

Would plugging in x=2 work? or should i do the latter

tmagloire1 · Answer

anyone?

tkhunny · Answer

No differentiation.
There is no such thing as "plugging in".  Try substitution.