The easiest way is to try the point (-4,1), that is, x=-4, y=1,
to see which equation works.
b works.
The usual way to do it is to find the equation of the circle
standard form of a circle is (x-h)²+(y-k)²=r², (h,k) are the coordinates of the center, r is the radius.
in this case, the center is (-2,1), so (x+2)²+(y-1)²=r²
the given point (-4,1) is for you to find r: (-4+2)²+(1-1)²=r², r=2
so the equation is (x+2)²+(y-1)²=2²
expand it: x²+4x+4+y²-2y+1=4
x²+y²+4x-2y+1=0, which is answer b.
The equation (form) is: 
The solution of the equation is: 
Explanation:
First, let's call the number we are going to solve for "x".
Then two thirds of this number can be written as:

Then "plus 4" means add 4 we get:

"is 7" means that the above expression is equal to 7 (as follows):

The solution of the above equation is:

Answer: 2/3^3
Step-by-step explanation:
To find the volume of a box, you use the formula, Lenth*Width*Height=Volume
The Lenth is 3 1/2. The width is 1 1/3 and the height is 2/14
Plug the values in formula
3 1/2*1 1/3*2/14
Covert the mixed numbers into imporper fractions so it is easier to solve
3 1/2=7/2
1 1/3=4/3
7/2*4/3*2/14
Reduce 2/14
2/14=1/7
7/2*4/3*1/7=7*4*1/(2*3*7)=28/42
Reduce 28/42=14/21=2/3
2/3 ft^3
Cone details:
Sphere details:
================
From the endpoints (EO, UO) of the circle to the center of the circle (O), the radius is will be always the same.
<u>Using Pythagoras Theorem</u>
(a)
TO² + TU² = OU²
(h-10)² + r² = 10² [insert values]
r² = 10² - (h-10)² [change sides]
r² = 100 - (h² -20h + 100) [expand]
r² = 100 - h² + 20h -100 [simplify]
r² = 20h - h² [shown]
r = √20h - h² ["r" in terms of "h"]
(b)
volume of cone = 1/3 * π * r² * h
===========================




To find maximum/minimum, we have to find first derivative.
(c)
<u>First derivative</u>

<u>apply chain rule</u>

<u>Equate the first derivative to zero, that is V'(x) = 0</u>




<u />
<u>maximum volume:</u> <u>when h = 40/3</u>


<u>minimum volume:</u> <u>when h = 0</u>

