SOLUTION: How to graph the ellipse y^2-6y+48x^2-3=0 Help me please :((

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Question 826517: How to graph the ellipse y^2-6y+48x^2-3=0
Help me please :((

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
y²-6y+48x²-3 = 0

You have to do algebraic operations on it to get it in the form:

%28x-h%29%5E2%2Fa%5E2%22%22%2B%22%22%28y-k%29%5E2%2Fb%5E2%22%22=%22%221

in which case it will look like this drawing%2820%2C10%2C-2%2C2%2C-1%2C1%2Carc%280%2C0%2C-3.9%2C1.9%29+%29,

or

%28x-h%29%5E2%2Fb%5E2%22%22%2B%22%22%28y-k%29%5E2%2Fa%5E2%22%22=%22%221

in which case it will look like this drawing%2810%2C20%2C-1%2C1%2C-2%2C2%2Carc%280%2C0%2C1.9%2C-3.9%29+%29

We won't know which it is until later, when we can see which
denominator is larger, for the larger denominator will be "a²" and 
the smaller denominator will be "b²".

y²-6y+48x²-3 = 0

Put the x term first, then the y terms second on the left 
of the equation and isolate the number on the right:

48x²+y²-6y = 3

Since there is no x-term, all we have to do is write the
term 48x² as 48(x-0)².

48(x-0)²+y²-6y = 3

Since there is a y-term we must complete the square on
y²-6y:

To the side, we
1. Multiply the coefficient of y, which is -6, by 1%2F2,
   getting -3.
2. Square the result of step 1 (-3)² = 9
3. Add +9 to both sides of the equation

48(x-0)²+y²-6y+9 = 3+9

Then we factor y²-6y+9 as (y-3)(y-3) and then as (y-3)²
and replace y²-6y+9 by (y-3)².  Combine the numbers on
the right side:

48(x-0)²+(y-3)² = 12

Then we divide through by 12 to get 1 on the right:

48%28x-0%29%5E2%2F12%22%22%2B%22%22%28y-3%29%5E2%2F12%22%22=%22%2212%2F12

48%28x-0%29%5E2%2F12%22%22%2B%22%22%28y-3%29%5E2%2F12%22%22=%22%221

We must get the 48 off the top of the first fraction.
To do that we divide top and bottom by 48:

expr%2848%2F48%29%28x-0%29%5E2%2Fexpr%2812%2F48%29%22%22%2B%22%22%28y-3%29%5E2%2F12%22%22=%22%221 

Simplify:

1%2A%28x-0%29%5E2%2Fexpr%281%2F4%29%22%22%2B%22%22%28y-3%29%5E2%2F12%22%22=%22%221

%28x-0%29%5E2%2Fexpr%281%2F4%29%22%22%2B%22%22%28y-3%29%5E2%2F12%22%22=%22%221

Now we can tell that it is an ellipse that looks like this drawing%2810%2C20%2C-1%2C1%2C-2%2C2%2Carc%280%2C0%2C1.9%2C-3.9%29+%29

because the larger denominator is a² which equals 12, and the
smaller denominator is b² which equals 1%2F4

So we compare it to:

%28x-h%29%5E2%2Fb%5E2%22%22%2B%22%22%28y-k%29%5E2%2Fa%5E2%22%22=%22%221

(h,k) = (0,3) is the center, 

Since a² = 12 then a = √12 = √4*3 = 2√ ≈ 3.46

Since b² = 1%2F4 then b = sqrt%281%2F4%29 = 1%2F2

a = the distance from the center (0,3) to the vertices, and b = the distance
from the center to the covertices.  So we plot the center, the vertices,
which are a ≈ 3.46, units above and bellow the center, and the covertices
which are 1%2F2 of a unit right and left of the center:



Then sketch in the ellipse (it's a tall skinny one!)

 

Edwin