Answer:
The initial population was 2810
The bacterial population after 5 hours will be 92335548
Step-by-step explanation:
The bacterial population growth formula is:

where P is the population after time t,
is the starting population, i.e. when t = 0, r is the rate of growth in % and t is time in hours
Data: The doubling period of a bacterial population is 20 minutes (1/3 hour). Replacing this information in the formula we get:





Data: At time t = 100 minutes (5/3 hours), the bacterial population was 90000. Replacing this information in the formula we get:



Data: the initial population got above and t = 5 hours. Replacing this information in the formula we get:


With the given information, we can create several equations:
120 = 12x + 2y
150 = 10x + 10y
With x being the number of rose bushes, and y being the number of gardenias.
To find the values of the variables, we can use two methods: Substitution or Elimination
For this case, let us use elimination. To begin, let's be clear that we are going to be adding these equations together. Therefore, in order to get the value of one variable, we must cancel one of them out - it could be x or y, it doesn't matter which one you decide to cancel out. Let's cancel the x out:
We first need to multiply the equations by numbers that would cause the x's to cancel out - and this can be done as follows:
-10(120 = 12x + 2y)
12(150 = 10x + 10y) => Notice how one of these is negative
Multiply out:
-1200 = -120x - 20y
+ 1800 = 120x + 120y => Add these two equations together
---------------------------------
600 = 100y
Now we can solve for y:
y = 6
With this value of y known, we can then pick an equation from the beginning of the question, and plug y in to solve for x:
120 = 12x + 2y => 120 = 12x + 2(6)
Now we can solve for x:
120 = 12x + 12 => 108 = 12x
x = 9
So now we know that x = 9, and y = 6.
With rose bushes being x, we now know that the cost of 1 rose bush is $9.
With gardenias being y, we now know that the cost of 1 gardenia is $6.
Answer:
(3, 13)
Step-by-step explanation:
i plugged the two lines into desmos :)
Answer:
Not necessarily. There are many ways to write a basic equation with a negative answer. For example, -3-4 = -7. Here 4 is a positive number but because you subtract 4 to 3 or take away 4 from 3 being a negative number and so you get a negative answer. Another example is 6+(-9). There are a couple of ways you can resolve this. My method is to subtract 9 from 6 which gives you 3 and simply add a negative sign.
Let me know if you'd like more examples. Hope this helps!! Sorry if it is confusing I can explain you in a more simpler way if you'd like.
Step-by-step explanation: