The formula used to find the length of a line segment is the same formula as the Pythagoras theorem.
We take CD as the hypotenuse of the right-angled triangle and the distance between the x-coordinates and y-coordinates as the length of two short sides.
We can write the formula as
CD =

CD =
Are you sure you wrote all the correct numbers because it does not work
Answer:
P ( snowboard I ski) = 0.5714
Step-by-step explanation:
Conditional Probability
We use the conditional probability formula to solve this question. It is

In which
P(B|A) is the probability of event B happening, given that A happened.
is the probability of both A and B happening.
P(A) is the probability of A happening.
In this question:
Event A: Ski
Event B: Snowboard.
28 out of 120 students ski:
This means that 
16 out of 120 do both:
This means that 
P ( snowboard I ski)

So
P ( snowboard I ski) = 0.5714
I am not sure if you have any choices. Here are some options:
0.17333333333
This is also notated by .1733 with a line over the top of the two 3's indicating that these number continue repeating.
Other choices depending on your instructions...
.173 (if rounded to thousanths)
.17 (if rounded to hundreths)
.2 (if rounded to tenths)
The y intercept is (0,-15)
https://www.desmos.com/calculator/xeyrlhyvt1