Which is the equation of a parabola with a directrix at y = −3 and a focus at (−2, 3).

y = (x + 2)²

Step-by-step explanation:

Any point on the parabola (x, y) is equidistant from the focus and directrix.

Using the distance formula

= | y + 3 |

Square both sides

(x + 2)² + (y - 3)² = (y + 3)² ← expand the factors in y

(x + 2)² + y² - 6y + 9 = y² + 6y + 9 ← subtract y² + 6y + 9 from both sides

(x + 2)² - 12y = 0 ← subtract (x + 2)² from both sides

- 12y = - (x + 2)² ( divide both sides by - 12 )

y = (x + 2)²

24+x=y

step-by-step explanation:

step-by-step explanation:

we can use this expression to calculate the energy gain as a particle moves with a field or the energy loss as it moves against it. (note that it is also used to define the electron-volt, a unit of energy equal to that gained by an electron as it falls through a pd of 1 v, i.e. w = 1 ev = 1.6 10-19 c 1 v = 1.6 10-19j).in fact this expression is really nothing more than the statement that potential is the potential energy per unit charge. in this case, v= w/qis simply stating that the change in potential energy(or work done) per unit charge is equal to the change in potential (or potential difference), v.student questions: uniform electric fields2electron beamcathode+5 kvanode0 v