Help please
|dw:1519269250970:dw| compare this w/ your equation to determine the center (h,k)
(-3,2)
(x-h)^2 = (x-2)^2 h = ?
vertices are (2,0)(2,-6)
-3
|dw:1519269470865:dw|
|dw:1519269476801:dw|
+3
notice how (x-2) = (x-h) just comparing them side by side what do you think h might be equal to?
hint: subtract x from both sides
-2?
almost -2 = -h h = ?
2
good, let's repeat this process to find k (y-k)^2 = (y+1)^2 k = ?
-1?
good so (h,k) = (2,-1) = your center
was this part 3?
we are still on part I (the center.)
oh okay
now, find the value of a by comparing the standard equation to the equation in the problem
|dw:1519270274987:dw|
compare these side by side, what's the value of a?
36?
close but not quite a^2 = 36, a = ?
6
good so the coordinates of the vertices are: (h+a,k), (h-a,k) plug in the h, a, and k values to get the coordinates
(2,0)(2,-6)
h = 2 k = -1 a = 6 re-try your calculations.
(8,-1)(-4,-1)
good for part III) we will need to calculate the value of b compare the equation in the problem w/ the standard form equation to find the value of b
(y+1)^2/25 = (y-k)^2/b^2 find b
if you just compare the denominators 25 = b^2 b = ?
5
good now, we need to find c c^2 = a^2 - b^2 for ellipses c = ?
** should also mention, leave it in radical form
(2,2)(2,-8)
would this be the foci?
no
calculate c where c^2 = a^2 - b^2 as a reminder, we determined a to be 6 and b to be 5
36-25=11^2=22
not sure where you're getting 22 from but yes, c^2 = 11 so c = sqrt(11) then the foci are just (h+c,k) and (h-c,k) so (2+sqrt(11), -1) and (2-sqrt(11),-1)
anyway, for IV we determined the vertices to be (8,-1)(-4,-1) major axis is along x, it's 2 * 6 = 12 units long minor axis is along y, it's 2 * 5 = 10 units long this should be sufficient to graph your ellipse
so it would be (12,0) and (0,10)
no the ellipse is not centered at 0 12 and 10 are the lengths of the axes not the coordinates of the vertices.
create an ellipse with vertices (8,-1)(-4,-1), major axis length 12, minor axis length 10.
would it just be the equation given
it is asking for a graph not an equation
|dw:1519272366586:dw|
|dw:1519272389968:dw|
|dw:1519272400272:dw|
using the information provided, graph the ellipse, labelling the vertices.
check the minor axis again if the center is (2,-1) then the ellipse crosses (2,-1+5) and (2,-1-5) so (2,4) and (2,-6)
good, that's about right
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