Find the axis of symmetry using the equation ##x=(-b)/(2a)##.
Find the vertex by substituting the value for ##x## into the equation and solving for ##y##.
There are no x-intercepts.
To get the y-intercept substitute 0 for ##x## in the equation and solve for ##y##.
##f(x)=-3x^2+3x-2##
The general formula for a quadratic equation is ##ax^2+bx+c##.
##a=-3##
##b=3##
The graph of a quadratic equation is a parabola. A parabola has an axis of symmetry and a vertex. The axis of symmetry is a vertical line the divides the parabola into to equal halves. The line of symmetry is determined by the equation ##x=(-b)/(2a)##. The vertex is the point where the parabola crosses its axis of symmetry and is defined as a point ##(xy)##.
Axis of Symmetry
##x=(-b)/(2a)=(-3)/(2(-3))=-3/-6=1/2##
The axis of symmetry is the line ##x=1/2##
Vertex
Determine the value for ##y## by substituting ##y## for ##f(x)## and by substituting ##1/2## for ##x## in the equation
##y=-3x^2+3x-2##
##y=-3(1/2)^2+3(1/2)-2##
##y=-3(1/4)+3/2-2##
##y=-3/4+3/2-2##
The common denominator is ##8##.
##y=-3/4*2/2+3/2*4/4-2*8/8## =
##y=-6/8+12/8-16/8## =
##y=-10/8##
##y=-5/4##
The vertex is ##(xy)=(1/2-5/4)##
X-Intercept
The x-intercepts are where the parabola crosses the x-axis.There are no x-intercepts for this equation because the vertex is below the x-axis and the parabola is facing downward.
Y-Intercept
The y-intercept is where the parabola crosses the y-axis. To find the y-intercept make ##x=0## and solve the equation for ##y##.
##y=-3(0)^2+3(0)-2## =
##y=-2##
The y-intercept is ##-2##.
graph{y=-3x^2+3x-2 [-14 14.47 -13.1 1.14]}

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