He equation of a parabola is x = -4(y-1)^2. What is the equation of the directrix?
<span>You may write the equation as </span>
<span>(y-1)^2 = (1) (x+4) </span>
<span>(y-k)^2 = 4p(x-h), where (h,k) is the vertex </span>
<span>4p=1 </span>
<span>p=1/4 </span>
<span>k=1 </span>
<span>h=-4 </span>
<span>The directrix is a vertical line x= h-p </span>
<span>x = -4-1/4 </span>
<span>x=-17/4 </span>
<span>------------------------------- </span>
<span>What is the focal length of the parabola with equation y - 4 = 1/8x^2 </span>
<span>(x-0)^2 = 8(y-4) </span>
<span>The vertex is (0,4) </span>
<span>4p=8 </span>
<span>p=2 (focal length) -- distance between vertex and the focus </span>
<span>------------------------------- </span>
<span>(y-0)^2 = (4/3) (x-7) </span>
<span>vertex = (7,0) </span>
<span>4p=4/3 </span>
<span>p=1/3 </span>
<span>focus : (h+p,k) </span>
<span>(7+1/3, 0)</span>
Answer:
If it has a diameter of 10, divide it by 2 to get Radius (5) because Area = πr²
Then you do r * π *r which would be 78.5. so C is your answer.
Step-by-step explanation:
ANSWER
The solution is
(x,y)=(1,-5)
EXPLANATION
The equations are:
1st equation: 6x +5y=-19
2nd equation: 12x-8y=52
Multiply the first equation by 2:
3rd equation: 12x +10y=-38
Subtracy the 2nd equation from the 3rd equations.
12x-12x+10y--8y=-38-52
18y=-90
Divide both sides by 18.
y=-5
Put y=-5 into any of the equations and solve for x.
Preferably, the first equation will do.
6x +5(-5)=-19
6x -25=-19
6x=25-19
6x=6
x=1
The solution is
(x,y)=(1,-5)
You're answers are correcy
12x+2y=112
6x+y=56
6x=56-y
x=(56-y)/6
y=(56-6x)
