SOLUTION: Find the vertex, line of symmetry, the maximum/minimum value of f(x). Then, graph the function. f(x) = -2(x+1)^2 + 8 Vertex is Line of symmetry Max/min value

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Find the vertex, line of symmetry, the maximum/minimum value of f(x). Then, graph the function. f(x) = -2(x+1)^2 + 8 Vertex is Line of symmetry Max/min value      Log On


   

Question 132084: Find the vertex, line of symmetry, the maximum/minimum value of f(x). Then, graph the function.
f(x) = -2(x+1)^2 + 8
Vertex is
Line of symmetry
Max/min value
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The form is f%28x%29+=+ax%5E2+%2B+bx+%2B+c
f%28x%29+=+-2%28x%2B1%29%5E2+%2B+8
f%28x%29+=+-2%28x%5E2+%2B+2x+%2B+1%29+%2B+8
f%28x%29+=+-2x%5E2+-+4x+-+2+%2B+8
f%28x%29+=+-2x%5E2+-+4x+%2B+6
a+=+-2
b+=+-4
The vertex is at %28-b%29%2F%282a%29
x+=+%28-%28-4%29%29%2F%282%2A%28-2%29%29
x+=+-1
Now find f%28x%29
f%28x%29+=+-2%28x%2B1%29%5E2+%2B+8
f%28x%29+=+-2%280%29%5E2+%2B+8
The vertex is at (-1,8)
The line of symmetry is x+=+-1
There is a maximum because the coefficient of x%5E2 is negative.
The max value is f%28x%29+=+8
Here's the plot:
+graph%28+600%2C+600%2C+-10%2C+3%2C+-10%2C+10%2C+-2x%5E2+-+4x+%2B+6%29+