Question 425433: Consider the Quadratic function . f(x)=3x^2-15x-18
its vertex is ( )
its largest x-intercept is x=( )
its y-intercept y=( ) Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! Consider the Quadratic function . f(x)=3x^2-15x-18
its vertex is ( )
its largest x-intercept is x=( )
its y-intercept y=( )
..
y=3x^2-15x-18
complete the square to put equation into standard form:
y=3(x^2-5x+25/4)-18-75/4
y=3(x-5/2)^2-147/4 (standard form with vertex at (5/2,-147/4
..
y-intercept, x=0
y=-18
..
x-intercept, y=0
3x^2-15x-18=0
=x^2-5x-6=0
=(x-6)(x+1)=0
x-6=0
x=6
x+1=0
x=-1
..
ans:
vertex (5/2,-147/4
y-intercept y=-18
x-intercepts:
x=6
x=-1
..
You can see all these parameters on the graph below:
(