Answer:
(x-3)^2 + (y+2)^2 = 9^2
Step-by-step explanation:
x^2 -6x+y^2+4y-68 = 0
Complete the square
x^2 -6x+y^2+4y-68+68 = 0+68
x^2 -6x+y^2+4y = 68
Find the term to add for x
-6 /2 = -3 -3^2 = 9
Find the term to add for y
4/2 =2 2^2 = 4
Add 9 and 4
x^2 -6x+9+y^2+4y+4 = 68+9+4
(x-3)^2 + (y+2)^2 = 81
(x-3)^2 + (y+2)^2 = 9^2
The standard form is
(x-h)^2 + (y-k)^2 = r^2 where (h,k) is the center and r is the radius
The correct answer is B) 9 m.
The measure of the sector of circle R is 32π/9 m. The measure of the central angle is 80°. This means that the sector is 80/360 = 2/9 of the circle. The area of a circle is given by A=πr², so the area of the sector is A=2/9πr². To verify this, 2/9π(4²) = 2/9π(16) = 32π/9.
Using this same formula for circle S, we will work backward to find the radius:
18π = 2/9πr²
Multiply both sides by 9:
18*9π = 2πr²
162π = 2πr²
Divide both sides by 2π:
162π/2π = 2πr²/2π
81 = r²
Take the square root of both sides:
√81 = √r²
9 = r
Try using the back of the book.
Answer:
16 hours
Step-by-step explanation:
let t be time, n the number of computers and w the number of workers, then
t = 
← k is the constant of variation
To find k use the condition n = 30, w = 6 and t = 10 , then
10 = 
( multiply both sides by 6 )
60 = 30k ( divide both sides by 30 )
2 = k
t = 
← equation of variation
When w = 5 and n = 40 , then
t = 
= 
= 16 hours
