Can anyone please help me with this?

The elevation of a hiking trail is modelled by the function h(x)=2x^3+3x^2−17x+12 where h is the height in meters above sea level and x is the horizontal distance from a ranger station in kilometers. If x<0, the position is to the west of the station, and if x>0 the position is to the east. Since the trail extends 4.2km to the west of the ranger station and 4km to the east, the model is accurate for {xεR|−4.2≤x≤4}. How can we determine which sections of the trail are above sea level?

a)

b)

Step-by-step explanation:

Given that function is a third order polynomial, it can be factorized:

The following inequation must be analyzed to determine which sections are above sea level:

By Algebra, it is known that product between three positive numbers or two negative numbers and a positive number are equal to a positive number. Then, there are only two trails:

a)

b)

the circle graph is not a function.

step-by-step explanation:

the graph of the circle is not a function.

because for a graph to be a function, each value of x must give one value of y

in the circle, the values of x for -2< x< 2 each give 2 values of y.

hence this is not a function.

for the friend request.

when a figure, such as triangle (xyz) is reflected over the line y = x to create x'y'z' the x-coordinates and y-coordinates of the original image (pre-image) will be reversed for the image. (e.g., (x, y) > (y, x)) this means that the pre-image position of the x- and y-coordinates switch places which in turn provides a mirror like image of the original xyz.  

i notice that when i draw a line segment from x to x', that the points are parallel from each other -- they are exactly across from each other and do not intersect with any other points.  

yes, think i would see the same characteristic if you drew the line segment connecting y with the reflecting line and then y' with the reflecting line because of the essence of reflections. because it is a mirror image, each point was effected the same way which leads me to conclude that they same would apply to y and y'.