Find the vertex, focus, directrix, and focal width of the parabola. (5 points) negative 1 divided by 16 times x squared = y

Step-by-step explanation:

Vertex: (0, 0); Focus: (0, -4); Directrix: y = 4; Focal width: 16 ⇒ answer (a)

Step-by-step explanation:

* Lets revise some facts about the parabola

- Standard form equation for a parabola of vertex at (0 , 0)

- If the equation is in the form  x² =  4py, then  

- The axis of symmetry is the y-axis,  x = 0  

- 4p  equal to the coefficient of y in the given equation to

 solve for  p

- If  p  >  0, the parabola opens up.

- If  p <  0, the parabola opens down.

- Use  p  to find the coordinates of the focus,  (0  ,  p)

- Use  p  to find equation of the directri ,   y= − p

- Use  p  to find the endpoints of the focal diameter,  (±2p  ,  p)

* Now lets solve the problem

- The vertex of the parabola is (0 , 0)

∵ -1/16x² = y ⇒ multiply each side by -16

∴ x² = -16y

∴ 4p = -16 ⇒ ÷ 4 tbe both sides

∴ p = -4

∵ The focus is (0 , p)

∴ The focus is (0 , -4)

∵ The directrix is y = -p

∴ The directrix is y = -(-4) = 4 ⇒ y = 4

∵ The endpoints of the focal diameter,  (±2p  ,  p)

∴ The focal width = 2p - (-2p) = 4p

∴ The focal width = 4 ×  I-4I = 16

* Vertex: (0, 0); Focus: (0, -4); Directrix: y = 4; Focal width: 16

22 dimes and 9 nickels

step-by-step explanation:

18

step-by-step explanation:

draw the shape and you will see that f and k are actually at adjacent vertices (points of the hexagon that are neighboring).   so find the distance between (1,2) and (4,2).   that is easy since (1,2) and (4,2) is just a vertical distance to count, which is 3.   it is a regular polygon which means all sides are congruent.   you have 6 sides (hexa) so multiply 6 by 3 to receive 18.