Use substitution
Plug in 5x for y
5x = 2x - 15
Subtract 2x
3x = -15
Divide by 3
x = -5, y = -25
Solution: (-5, -25)
To draw the 2 dimensional representation, we just "open" the box and flatten it. Once we have it opened, we find the area of each side and add them up for the total surface area. See the pic. Let me know if you have questions. :)
Answer: The probability that a randomly selected tire will have a tread-life of less than 65,000 miles is 0.7872 .
Step-by-step explanation:
The cumulative distribution function for exponential distribution is :-
, where
is the mean of the distribution.
As per given , we have
Average tread-life of a certain brand of tire : 
Now , the probability that a randomly selected tire will have a tread-life of less than 65,000 miles will be :

Hence , the probability that a randomly selected tire will have a tread-life of less than 65,000 miles is 0.7872 .