Questions on Algebra: Trigonometry answered by real tutors!

You can put this solution on YOUR website!
16x^2=y.
There are 4 choices for an answer:
1. Focus (0,4), directrix y=-4
2. Focus (0,1/4), directrix y=-1/4
3. Focus (0,1/16), directrix y=-1/16
4. Focus (0,1/64), directrix y=-1/64
Thank you for your time and help, Natalie!
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The standard from for parabolas is x^2=4py
So y = x^2/4p = 16x^2
x^2/4p = 16x^2
4p = x^2/16x^2 = 1/16
p = 1/64
P is the distance from the Origin to the directrix, and (0,p) is the focus.
That's answer #4.

Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)

Quadratic equation ax^2+bx+c=0

(in our case 16x^2+0x+0 = 0

) has the following solutons:

$x[12] = (b+-sqrt( b^2-4ac ))/2\a$

For these solutions to exist, the discriminant b^2-4ac

should not be a negative number.

First, we need to compute the discriminant b^2-4ac

.

Discriminant d=0 is zero! That means that there is only one solution: $x = (-(0))/2\16$ .
Expression can be factored: 16x^2+0x+0 = (x-0)*(x-0)

Again, the answer is: 0, 0. Here's your graph:
graph( 500, 500, -10, 10, -20, 20, 16*x^2+0*x+0 )