Answer:
The x intercepts are 2, -4
The y intercept is -8
The minimum is -9
Explanation:
f(x)=x^2+2x-8
To find the x intercepts, set equal to zero and factor
0 =x^2+2x-8
0 = (x+4)(x-2)
Using the zero product property
0 = x+4 0 = x-2
x = -4 x = 2
The x intercepts are 2, -4
To find the y intercepts, set x =0 and solve for y
y = 0^2 +2(0) -8
y = -8
The y intercept is -8
Since the coefficient of the x^2 is positive, the parabola opens up so we have a minimum.
The vertex is halfway between the x intercepts
(-4+2)/2 = -2/2 = -1
To find the minimum substitute x= -1 into the equation
f(x)=x^2+2x-8
f(-1) = (-1)^2 +2(-1)-8 = 1-2-8 = -9
The minimum is -9