First, let
be a point in our parabola. Since we know that the focus of our parabola is the point (0,8), we are going to use the distance formula to find the distance between the two points:
Next, we are going to find the distance between the directrix and the point in our parabola. Remember that the distance between a point (x,y) of a parabola and its directrix,
, is:
. Since our directrix is y=-8, the distance to our point will be:
Now, we are going to equate those two distances, and square them to get rid of the square root and the absolute value:
Finally, we can expand and solve for
:
We can conclude that t<span>he standard form of the equation of the parabola with a focus at (0, 8) and a directrix at y = -8 is </span>
Answer:
Step-by-step explanation:
Given that prices for a pair of shoes lie in the interval
[80,180] dollars.
Delivery fee 20% of price.
i.e. delivery fee will be in the interval [4, 9]
(1/20th of price)
Total cost= price of shoedelivery cost
Hence f(c) = c+c/20 = 21c/20
The domain of this function would be c lying between 80 to 180
So domain =[80,180]
---------------------------------
Amount to be repaid = 42 dollars
Once he received this amount, the price would be
105+42 =147
But since price range is only [21*80/20, 21*180/20]
=[84, 189]
Since now Albert has 147 dollars, he can afford is
[80,147]
5.77
By 0.07
Because if you subtract 0.07 from 5.77, you get 5.7, so it must be smaller.