Find the standard form of the equation of the ellipse and give the location of its foci.
please explain
Do you know how to find major axis and minor axis?
no ma'am
major axis= 2a, minor axis=2b
look at the graph
looking o.o
do you know where the major axis is?
half of the value of the major axis is a (we need a and b for the equation)
semi-major axis is 7 and the semi-minor is 6.
yes :)
7 is a and 6 is b
the standard equation for an ellipse ( in this case it is vertical ellipse because the major axis is in the y axis) \[\frac{ x^{2} }{ b^{2} } + \frac{ y^{2} }{ a^2 }=1\]
So I'm supposed to plug in the major axis and the minor axis into a and b? and if the major axis is in the x-axis it's a horizontal ellipse?
\(\Large \frac{ x^{2} }{ a^{2} } + \frac{ y^{2} }{ b^2 }=1 \) You can quickly verify where 'a' and 'b' should be by setting y = 0 and finding the x-intercepts or setting x = 0 and finding the y-intercepts.
yes
I see... do the x and y need numbers plugged into them too?
no
Plug in values for 'a' and 'b'.
can you tell us what you get for the equation?
when you plug in
The major axis is along x-axis so 'a^2' should go under the x-term.
\[\frac{ x^2 }{ 49 } + \frac{ y^2 }{ 36 } = 1\]
oops sorry about that
o.o dang it
yes that is correct
Ooooh lol sorry
but your equation is correct ^_^
thank you guys...what do I do next? o.o
ok now let's find the Foci
Foci of a Horizontal ellipse: (h+-c,k)
The vertex is (h,k), for this ellipse, its vertex is at the origin (0,0)
Woah there...sorry I just got confused e.e
oh wait nvm I see it
the foci of a horizontal ellipse: (h+-c,k) the +- means plus or minus)
to find c you use: \[ c^{2}=a^{2}-b^{2}\]
\[c^2 = 7^2 - 6^2\] then shouldn't c^2 be 1^2 ? but in my calc I did 49 - 36 and got 13... would I make that \[\sqrt{13}\]
yes
Yes. One focus at \(\large (+\sqrt{13}, 0) \) and another at \(\large (-\sqrt{13}, 0) \)
I agree with aum
FYI: In a parabola (h,k) is the vertex. In ellipse and hyperbola, (h,k) is the center.
correct,lol sorry, I am in pre-calculus hehe I'm learning as well,but thank you aum :)
Thank you both ^-^ I wish I could give you both medals /.\ I appreciate your help <3
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