Need derive the equation of the parabola with a focus at (2, −1) and a directrix of y = −one half.

The equation of required parabola is .

Step-by-step explanation:

The standard form of a parabola is

Where, (h,k) is vertex, (h,k+p) is focus and y=k-p is directrix.

It is given that the focus of the parabola is at (2,-1).

                .... (1)

The directrix of the parabola is

            .... (2)

Add equation (1) and (2).

Divide both sides by 2.

Put this value in equation (1).

Substitute h=2, and in the standard form of the parabola.

Therefore the equation of required parabola is .

answer: d. $20

step-by-step explanation:

just took the test

i think the answer is seven, for if i'm being useless °ω°

step-by-step explanation: