Question

Find the x-intercepts and y-intercept for the parabola below. Write answers as (x,y) coordinates.
y=2x2-4x-6
x-int:_____________ y-int:_______

Answer 1

assuming the function is $y=2x^2-4x-6$
the x intercepts are where the graph hits the x axis or where y=0
the y intercepts are where the graph hits the y axis or where x=0


x intercepts
set y=0 and find x
$0=2x^2-4x-6$
$0=2(x^2-2x-3)$
what 2 numbers multiply to get -3 and add to get -2?
-3 and 1
$0=(2)(x-3)(x+1)$
set to 0
0=x-3
3=x
0=x+1
-1=x

x intercepts are at x=-1 and 3 or the points (-1,0) and (3,0)



y intercepts are where x=0
set x=0
$y=2(0)^2-4(0)-6$
$y=0-0-6$
$y=-6$
y intercept is at (0,-6)



x intercepts are at (-1,0) and (3,0)
y intercept is at (0,-6)