Given that the directrix is at y = 4 and the focus is at (0, -4), then the vertex is at (h, k) = (0, 0).
p is the distance between the vertex and the focus and between the vertex and the directrix = 4 and since the focus is below the directrix, p is negative, i.e. p = -4
Equation of a parabola is given by (x - h)^2 = 4p(y - k)
Therefore, the required equation is (x - 0)^2 = 4(-4)(y - 0)
x^2 = -16y
y = -1/16 x^2
Answer:
21
ctto JBarnum
Step-by-step explanation:
P+11=(1/2)(P-13)^2
P+11=(1/2)(P^2-26p+169)
2(P+11)=(1/2)(2)(P^2-26p+169)
2P+22=P^2-26p+169
0=P^2-28p+147 ( -7 and -21)
(P-7)(P-21)=0
P=7,21 (cant be 7 as 13 years from 7 is negative so peter is 21)
checking:
21+11=32
32=(1/2)(21-13)^2
32=(1/2)(8)^2
32=(1/2)64
32=32
correct
Answer:
The answer to your question is: ≈ 178 balls
Step-by-step explanation:
Data
rectangular prism = 8 in x 11 in x 5 in
golf balls = 1.68 in diameter
Formula
Volume rectangular prism = l x w x h = 8 x 11 x 5 = 440 in³
Volume of ball = (4/3) πr³ = (4/3) (3.1416) (0.84)³ = 2.48 in³
# of balls inside the compartment = volume rectangular prism / volume ball
# of balls = 440 / 2.48
= 177.4 ≈ 178 balls
36 inches because 12,24,36 and 18,36, 36=36
Answer:
it should be 23 feet long
Step-by-step explanation: