Given (2,1),(0,-2),(-2,-3), what is the coordinate of the y intercept, the slope and equation of the line?
1 Answer
Apr 14, 2015
Assuming the line is a standard (non-rotated) parabola
it has the form:
Using the given points
we can write three equations in three unknowns (
#1=4a +2b +c# #-2 =0a +0b +c# #-3 = 4a-2b+c#
From equation 2
and by inspection or standard operations it follows that
The equation of the parabola is therefore
We were told the y-intercept (it's the point where
The y-intercept is
We are not given a point at which to evaluate the slope (I'm assuming it is the slope of the tangent that is being asked for)
so the best we can do is give the general formula for the slope at a point
namely the derivative of