Question 441899: Find the values of a,b,and c such that the parabola y=ax^2+bx+c contains the points (-3,3),(-1,5)and (3,33). Answer by Gogonati(855) (Show Source):
You can put this solution on YOUR website! Plugging the coordinates of the points into , we get the system:
. Subtracting first equation from
the third we get: => .Isolate c from the first and second
equation:c=3-9a+3b and c=-1-25a-5b, from these two equalities we get:
3-9a+3b=-1-25a-5b simplifying this equality we get:4a+2b=-1, substituting b=5,
we have: 4a+2*5=-1 => a=-11/4. Substituting a and b we find c:
c=3+99/4+15 => c=171/4.
You can solve the system using Cramer's Rule.
Done.