The line is called the directrix. Here we have a vertical directrix, so a parabola sideways from usual.
Geometry is best done with squared distances. The squared distance from an arbitrary point (x,y) to the vertical line x=2 is
We equate that to the squared distance of (x,y) to the focus (-2,0):
We could call that done. A more standard form might be
<h3>
<u>Explanation</u></h3>
- Given the system of equations.
- Substitute x = 4 in the first equation.
We have both x and y values. Therefore, we can answer in coordinate point form.
<h3>
<u>Answer</u></h3>
<u>
</u>
Sold 2/5 in the morning.....leaving 3/5
he sold 3/4 of 3/5 in the afternoon......3/4 * 3/5 = 9/20
2/5 = 8/20
9/20 - 8/20 = 1/20...so he sold 1/20 more in the afternoon.
so if 1/20 = 24, then 20/20 = 24*20 = 480
so he started with 480 cartons
Your answer would be x= -42
<h3>
Answer: 0.157</h3>
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Explanation:
Convert the fraction 9/50 to decimal form. You can use either long division or a calculator.
You should find that 9/50 = 0.18 which is the same as 0.180
So the original compound inequality is the same as saying 0.125 < x < 0.180
This tells us that x is between 0.125 and 0.180 where x is not equal to either endpoint. We simply need to pick anything in this interval. It can be anything you want (I recommend to use a number line to help pick a value). One such value is 0.157. There are infinitely many values you can select from.
The number 0.157 is between 0.125 and 0.180, ie 0.125 < 0.157 < 0.180
It's very similar to saying 157 is between 125 and 180, ie 125 < 157 < 180.
