SOLUTION: Conics: Equation: 16y^2=49x^2+784 I need all necessary parts and need to know which conic it is

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Question 973502: Conics: Equation: 16y^2=49x^2+784
I need all necessary parts and need to know which conic it is

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
16y%5E2=49x%5E2%2B784
The original equation can be transformed into an equivalent form
that will make all you need to know very clear.
16y%5E2-49x%5E2=784
It so happens that 16%2A49=784 ,
one of those lucky coincidences that happen very often in math homework.
%2816y%5E2-49x%5E2%29%2F784=784%2F784
16y%5E2%2F784-49x%5E2%2F784=1
y%5E2%2F49-x%5E2%2F16=1
y%5E2%2F7%5E2-x%5E2%2F4%5E2=1
It is clear from the last equation above that for x=0 , system%28y=-7%2C%22or%22%2Cy=7%29 .
You can also see that since x%5E2%2F4%5E2%3E%2B0 ,
it must be true that y%5E2%2F7%5E2%3E=1<--->y%5E2%3E=7%5E2 for all the points in the graph.
That means that the horizontal band with -7%3Cy%3C7 is a forbidden zone that the graph does not enter.
It also means that the points (0,-7), and (0,7) found above are the vertices, and that this is a hyperbola.
y%5E2%2F7%5E2-x%5E2%2F4%5E2=1<--->y%5E2%2F7%5E2=x%5E2%2F4%5E2%2B1<--->y%5E2=7%5E2x%5E2%2F4%5E2%2B7%5E2<--->y%5E2%2Fx%5E2=7%5E2%2F4%5E2%2B7%5E2%2Fx%5E2 also makes it clear that as x%5E2 increases,
the curve approaches the lines where
y%5E2%2Fx%5E2=7%5E2%2F4%5E2<--->system%28y%2Fx=7%2F4%2C%22and%22%2Cy%2Fx=-7%2F4%29<--->system%28y=%287%2F4%29x%2C%22and%22%2Cy=%28-7%2F4%29x%29 .
Those two straight lines are the asymptotes.
So far we know that the curve looks like this
,
a smile and a frown tangent on the oustside to the horizontal lines system%28y=-7%2C%22and%22%2Cy=7%29 ,
all symmetrical with respect to the x-axis and the origin, (0,0).
All that is left to do, is to draw that rectangular box bounded by the lines
system%28y=-7%2C%22and%22%2Cy=7%29 , and realize that the half sides, and half diagonals of that box area the a , b and c that they showed you in formulas in math class,
a , and b being the numbers that appear squared as denominators in ,
and c being the distance from the center, (0,0), to the foci, at (0,-c), and (0,c).
In the right triangle, c%5E2=7%5E2%2B4%5E2<-->c%5E2=65-->c=sqrt%2865%29