Question

Find the vertex, the line of symmetry, the maximum of the quadratic function, and the graph function. f(x)=-2x^2+2x+5
What is the x-coordinate of the vertex?

Answer 1

x = -b/2a x = -2/-4=1/2
y=-2(1/2)^2 +2(1/2) +5
y = -1/2+1+6=5.5
Vertex is (1/2,11/2)
Line of symmetry goes through the vertex and is vertical so x = 1/2
The maximum is the y coordinate of the vertex so 11/2
The graph contains the vertex, the y intercept of 5, (2,1) (3,-7). Using symmetry, that should be enough to graph it. The x coordinate of the vertex is 1/2