I'm assuming that you mean

because if you meant

then u would simplify and you couldn't make it the subject.
Under this assumption, we start with

We multiply both sides by 

We expand the left hand side:

We move all terms involving u to the left and all terms not involving u to the right:

We factor u on the left hand side:

We divide both sides by 

Answer:
$65
Step-by-step explanation:
Let's add up the flat rate and the cost of four tires:
flat rate + 4($122.57/tire) = $555.28
We are to solve for "flat rate." First, multiply out 4($122.57/tire), obtaining a tire cost of $490.28 total. Subtracting this tire cost from the $555.28 Janette paid the shop, we get "flat rate" = $555.28 - $490.28, or $65.
Thus, the installation charge ("flat rate") must have been $65.
Answer:
<em>99.93%</em>
Step-by-step explanation:
<u>Probability of Independent Events</u>
Given the probability of success of each detector is 0.84 independently of the others, their combined success/failure probability can be computed with the product rule.
We can calculate the required probability by using the binomial distribution, but it's easier to calculate the probability of the negated event an subtract from 1.
We want to know the probability that a least one of the 4 systems detects the occurrence of theft. That probability is the sum of the probabilities that one of them, two of them, three of them or all of them succeed. The negated event is that NONE of them actually detects the theft. Being p the individual probability of success, p=0.84. Being q the probability of failure, q=0.16.
The probability that none of the systems detect the theft is

Thus, the probability that at least one of the systems detect the theft is

That means a 99.93%
Your answer would be 15.6