the "c" equations (just need to know one "c" for any one of the equations, doens't matter):
y=cx
y=cx^2
y=c square root of absolute x
y= c/x
the points are (-4,-1) (-1, -.25) (0,0) (1, .25) (4,1) ???
How can i find what "c" is in one of these equations if i know the points on the graph?
e.g.
points (x, y) = (-4 ,-1) so first equation
-1 =c*(-4) = -4c
c = 1/4
2) y = cx^2 implies
-25 = c* (-1)^2 = c*1 = c
so c = 25
--------------------------------------...
P.S.
ok, i get your point, if all these points are in a graph, then we can find the 'c' which is the slope (gradient of that graph)
i.e y = mx + 'k' , where 'm = c' in this case is usually the slope and 'k' is a constant
so pick any two points (x1, y1) and (x2, y2)
c = (y2 - y1 )/ (x2 - x1)
so if we pick the first two points,
c = (-25 - (-1) )/ (-1 - (-4))
= (-25 + 1) / (-1 +4)
= -24/3 = -8
so your 'c' = -8 iff these two particular points are in a graph.
eqn of the line is
y - y1 = c (x - x1), for give points (x1, y1)
pick any of the pair of points we have used to get 'c'
say (-4, -1) = (x1, y1)
y = cx + k
to find 'k' take (-4 , -1) = (x , y)
so (-1) = (-8)*(-4) + k
hence 'k' = -33
thus
equation of the graph passing through these two points is
y = - 8*x - 33
Clearly not one of the equations you have there ... so try another paring, let me think of a shorter way to get around the problem, mean while i hope you get the idea ...
Reply:c = (-3,7)
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