Answer:
HI
Step-by-step explanation:
ANSWER

EXPLANATION
Since the directrix is

the axis of symmetry of the parabola is parallel to the y-axis.
Again, the focus being,

also means that the parabola will open upwards.
The equation of parabola with such properties is given by,

where

is the vertex of the parabola.
The directrix and the axis of symmetry of the parabola will intersect at

The vertex is the midpoint of the focus and the point of intersection of the axis of the parabola and the directrix.
This implies that,

and

The equation of the parabola now becomes,


Thus, the distance between the vertex and the directrix.
This means that,

Since the parabola opens up, we choose

Our equation now becomes,

This simplifies to

or

This is the same as,

The correct answer is D .
Answer:
8/19 if you turn it into a inproper fraction.
Step-by-step explanation:
Answer:
19.365
Step-by-step explanation:
The Pythagoreum Theorum tells us that:
a² + b² = c²
where a and b are the legs and c is the hypotenuse.
BC is a leg; we'll lable it a.
AC is the hypotenuse thus labled c.
Plugging their lengths into the above formula will solve for the missing leg length.
5² + x² = 20²
25 + x² = 400
x² = 375
✓x = ✓3 x (5 x 5) x 5
x = 5✓15
x = 19.365