Answer:
39 feet
Step-by-step explanation:
From the question;
let length of ladder =x feet
height of ladder will be=x-3 feet
ground distance of ladder bottom to building=15 feet
Applying Pythagorean relation
a²+b²=c²
where a=15 feet b=x-3 feet and c=x feet thus
x²-15²=(x-3)²
x²-225=x²-6x+9
collect like term
x²-x²-225-9=-6x
-234= -6x
x= 39 feet length of ladder
distance from ground to top of ladder= 39-3=36 feet
Easy
sub 2 for x
f(2)=2(2)^3-3(2)^2+7
f(2)=2(8)-3(4)+7
f(2)=16-12+7
f(2)=11
Answer:
10 oranges
Step-by-step explanation:
Since the four friends each got 2, there must have been 8 oranges to distribute. That was 2 fewer than Felix started with, so ...
Felix started with 10 oranges.
Answer:
a)
X | 1 3 5 7
f(X) | 0.4 0.2 0.2 0.2
b) 
Step-by-step explanation:
For this case we have defined the cumulative distribution function like this:





And we know that the general definition for the distribution function is given by:

Where f represent the density function.
Part a
For this case we need to find the density function, so we can find the values for the density for each value of X = 1,2,3,4,5,6,7,... since X is a discrete random variable.







And for any value higher than 7 we have that:
![x_i \in [8,9,10,...]](https://tex.z-dn.net/?f=%20x_i%20%5Cin%20%5B8%2C9%2C10%2C...%5D)

So then we have our density function defined like this:
X | 1 3 5 7
f(X) | 0.4 0.2 0.2 0.2
Part b
For this case we want to find this probability 
And since the random variable is discrete we can write this like that:

Intersection mean what are the common number so in my point of view the intersection will be (33,77).i think its 100% right