Answer:
0.9898 = 98.98% probability that there will not be more than one failure during a particular week.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
e = 2.71828 is the Euler number
is the mean in the given interval.
3 failures every twenty weeks
This means that for 1 week, 
Calculate the probability that there will not be more than one failure during a particular week.
Probability of at most one failure, so:

Then



Then

0.9898 = 98.98% probability that there will not be more than one failure during a particular week.
the side x is 15
bottom right angle is 31.61 degrees
other angle is 58.39 degrees
Answer:y+7x=8
Step-by-step explanation:y=-7x+8
7x needs to be on the variable side
y+7x=8
Could you take a little bit clear picture? :)