Answer:
I believe 4 but I'm not that good at math but 4
I believe you need to solve this using the quadratic formula!
To begin, this is what it is:
x= -b ± <span>√ b^2 - 4ac / 2a
Just plug in what you have in your problem...
2 being a, 13 being b, and -24 being c.
So we get:
x= -13 </span>± <span>√13^2 - 4(2)(-24) / 2(2)
x= -13 </span><span>± √169 - 8 (-24) / 4</span>
<span>x= -13 <span>± √169 + 192 / 4</span>
x= -13 </span>± √<span>361 / 4
The square root of 361 is 19.
So you have: -13 </span><span>± 19 / 4.
Here's where you take the equation </span>-13 <span>± 19 and put the addition and subtraction sign to use.
-13 - 19 = -32
and
-13 + 19 = 6
Now all is left to do is divide the two numbers by 4.
-32/4 = -8
and
6/4 = 3/2
x = -8, 3/2</span>
The correct answer would be (C.) x>90
Answer:
The amount of oil was decreasing at 69300 barrels, yearly
Step-by-step explanation:
Given


Required
At what rate did oil decrease when 600000 barrels remain
To do this, we make use of the following notations
t = Time
A = Amount left in the well
So:

Where k represents the constant of proportionality

Multiply both sides by dt/A


Integrate both sides


Make A, the subject

i.e. At initial
So, we have:






Substitute
in 

To solve for k;

i.e.

So:

Divide both sides by 1000000

Take natural logarithm (ln) of both sides


Solve for k



Recall that:

Where
= Rate
So, when

The rate is:


<em>Hence, the amount of oil was decreasing at 69300 barrels, yearly</em>