Answer:
The equation of the parabola is 
.
Step-by-step explanation:
Since the directrix is of the form 
, the parabola is vertical. The vertex of the parabola (
) is the midpoint between the focus (
) and a point of the directrix (
), that is to say:
(1)
If we know that 
and 
, then the coordinates of the vertex of the parabola:
The vertex factor (
) is the distance of the focus with respect to the vertex:
![p = \sqrt{[F(x,y)-V(x,y)]\,\bullet \,[F(x,y)-V(x,y)]}](https://tex.z-dn.net/?f=p%20%3D%20%5Csqrt%7B%5BF%28x%2Cy%29-V%28x%2Cy%29%5D%5C%2C%5Cbullet%20%5C%2C%5BF%28x%2Cy%29-V%28x%2Cy%29%5D%7D)
(2)
If we know that and , then the vertex factor is:
The equation of the parabola in the vertex form is described below:
(3)
Where:
- Independent variable.
- Dependent variable.
- Coordinates of the vertex.
If we know that 
and , then the equation of the parabola is .
Use the Pythagorean theorem
to find the missing side length of a right triangle
In this case, after you plug in the given numbers your equation is
Then, Just solve that equation for y.
y = 16
So the answer is B, 16 cm.
I hope this helps, please feel free to ask questions if you're still confused :)
To find the area of a rectangular prism multiply length by width by height.
If the problem has a variable take the two other dimensions and multiply them together. Then take that number and subtract it from the total to find the number that the variable equals.
48 girls are there. Given that there is a ratio of boys to girls of 7:8. Then divide 42 boys by 7 boys which equals 6. After, multiply 6 by 8 girls equals 48 girls.
