Answer:
The graph is attached.
Step-by-step explanation:
- To help you to construct the graphic yourself, it is useful to find the roots of the equation (the values of x that make y=0). In this case, because we have a equation of grade three, we will find three roots.
- It is very simple to find the roots of this equation, just ask yourself: which values of x makes y=0?
- To find the three roots, we should equal y to zero and see what values of x respect the equality:
⇒
.
will be true only under three values of x: x=1 (
, x=(-1)(
) and x=0 (
.- Finally, to know how to finish our graph, we should marked the roots in the x axis, we have four important intervals to analyse defined by our roots: (-∞, -1); (-1,0); (0;1) and (1,∞). We should check if the function takes possitive or negative values within this intervals, and this will give us an idea of how to join the different points defined by the roots.
- As an example, if we take x=-10 ( a number of the first interval), the function will take the value of y=-900. If we do this with others values of this interval we will notice that they are all negative, wich means that the function increases to reach y=0 at the point where x=-1.
- You can check points in the others intervals to see how you finally unite all the points and get the graph below.
Mean (μ) = 11.5 feet
Standard deviation (σ) = 1.7 feet
First we need to find the z-score for less than 13.5 feet.
The formula of z-score is : z = (X - μ)/σ
Here X= 13.5, so z = 
z =
= 1.18
P(X < 13.5) = P(z< 1.18) =P(z< (1.1 + .08)) = 0.8810 (from z-score table)
P(X< 13.5) = 88.1% (for making percentage from decimal, we need to multiply by 100)
So, the probability that a randomly selected tree is less than 13.5 feet tall = 88.1%
Answer:
a
Step-by-step explanation:
Answer:
Step-by-step explanation:
If the value a is positive in the linear equation y = a x ( for example: y = 2 x ) then the line ( from the left to the right ) must go up and to the right. It also passes through the origin ( 0, 0 ). For x = 1: y = 2 * 1 = 2, so that point is ( 1, 2 ), x2 > x1, and y2 > y1.Answer:A. goes up and to the right.