SOLUTION: I need help finding the vertex of the parabola f(x)=-x2+3x-1

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: I need help finding the vertex of the parabola f(x)=-x2+3x-1      Log On


   

Question 129813: I need help finding the vertex of the parabola
f(x)=-x2+3x-1
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29+=+-x%5E2+%2B+3x+-+1
The x value at the vertex is -%28b%2F2a%29
when equation is in the form y+=+ax%5E2+%2B+bx+%2B+c
a+=+-1
b+=+3
-%28b%2F2a%29+=+-%283%2F%282%2A%28-1%29%29%29
-%28b%2F2a%29+=+3%2F2
f%28x%29+=+-x%5E2+%2B+3x+-+1
f%283%2F2%29+=+-%283%2F2%29%5E2+%2B+3%283%2F2%29+-+1
f%283%2F2%29+=+-%289%2F4%29+%2B+18%2F4+-+4%2F4
f%283%2F2%29+=+5%2F4
The vertex is at (3/2,5/4)
+graph%28+700%2C+700%2C+-2%2C+5%2C+-2%2C+3%2C+-x%5E2+%2B+3x+-+1%29+