Find the equation of the parabola whose axis is parallel to y-axis and which passes through the points (0,4) (1,9) (-2,6) and determine its latus rectum.???
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2 Answers
1as axis is paralle to y axis
the general form =
(x-h)2=4a(y-k)
when x=0 y=4
hence putting the values
h2=4a(4-k)
when x=1 y=9
hence
(1-h)2=4a(9-k)
when x=-2,y=6
hence (h+2)2=4a(6-k)
now multiply the third equation by (-5/2) and add it to the second equation
u will get
5/2(h-2)2-(h-1)2=(3/2)4a(4-k)
but 4a(4-k)=h2
so we get h=-3/4
now youve got h so u will get the aother two variables just by replacing this value in other equations
