Answer:
-6
Step-by-step explanation:
Add 2 to -26 to get -24. Divide -24 by 4 to get -6
Standard form is, hold a sec
x=2 is directix
that means it opens left or right
so we must use
(y-k)²=4p(x-h)
where vertex is (h,k) and p is distance from focus to vertex
also shortest distance from vertex to directix
the shortest distance from focus to directix is 2p
if p>0 then the parabola opens right
if p<0 then pareabola opens left
so
(-2,0) and x=2
the distance is 4
4/2=2
p=2
wait, positive or negative
focus is to the left of the directix so p is negative
p=-2
vertex is 2 to the right of the focus and 2 to the left of directix
vertex is (0,0)
so
(y-0)²=4(-2)(x-0) or
y²=-8x is da equation
not sure what form is standard tho
Answer:
5$??.
Step-by-step explanation:
If a magazine was 5$, 25-5= 20. So then, 20÷4= 5. There fore an eraser costs 5$.
Cvol=hpir^2
d/2=r
10/2=5=r
h=2.3
pi=aprox 3.141592
v=2.3*3.141592*5^2
v=180.64
round to tenth
v=180.6 cubic inches
Answer:
Length = 4cm
Width = 4cm
Height = 8cm
Step-by-step explanation:
The volume of the box = 128cm^3
LWH = Volume
LWH = 128cm^3
The side of the box = $1 per cm^2
The top and bottom of the box = $2 per cm^2
Let C be the cost function
C(LWH) = (1) 2H (L+W) + (2) 2LW
from LWH = 128cm^39
H = 128/LW
put H = 128/LW in equation for C(LWH)
C(LW) = (1) 2(128/LW) + (L+W) +(2) 2LW
= 256/LW(L+W) + 4LW
= 256(1/L + 1/W) + 4LW
Differentiate C with respect to L
dC/dL = 4W - 256/L^2 = 0
Differentiate C with respect to W
dC/dW = 4L - 256/W^2 = 0
The cost is minimum when the two partial derivatives equal 0
From 4W - 256/L^2 = 0
4W = 256/L^2
W = (256/L^2) 1/4
W = 64/L^2
From 4L - 256/W^2 = 0
4L = 256/W^2
L = (256/W^2) 1/4
L = 64/W^2
Since L = W,
L= W = cuberoot (64)
L = W = 4cm
Recall that H= 128/LW
H = 128/(4*4)
H= 128/16
H= 8cm
therefore;
L= 4cm
B= 4cm
H= 8cm
