If the order does not matter, then this is a combinations question. The number ways is calculated by
₅C₂ = 5!/[ (5-2)! * 2! ] = 10
There are 10 ways.
No they do not form a proportion. If i'm wrong i'm sorry. Maybe I did my math wrong but I don't think they form a proportion .
600 * 0.85 (the way to work out 85% of something) = 510 flights on time
1.) 24% 24/100 0.24
2.) 7% 7/100 0.07
3.) 36% 36/100 (9/25) 0.36
4.) 20% 20/100 (1/5) 0.20
5.) 15% 15/100 (3/20) 0.15
Answer:
We know that the equation of the circle in standard form is equal to <em>(x-h)² + (y-k)² = r²</em> where (h,k) is the center of the circle and r is the radius of the circle.
We have x² + y² + 8x + 22y + 37 = 0, let's get to the standard form :
1 - We first group terms with the same variable :
(x²+8x) + (y²+22y) + 37 = 0
2 - We then move the constant to the opposite side of the equation (don't forget to change the sign !)
(x²+8x) + (y²+22y) = - 37
3 - Do you recall the quadratic identities ? (a+b)² = a² + 2ab + b². Now that's what we are trying to find. We call this process <u><em>"completing the square"</em></u>.
x²+8x = (x²+8x + 4²) - 4² = (x+4)² - 4²
y²+22y = (y²+22y+11²)-11² = (y+11)²-11²
4 - We plug the new values inside our equation :
(x+4)² - 4² + (y+22)² - 11² = -37
(x+4)² + (y+22)² = -37+4²+11²
(x+4)²+(y+22)² = 100
5 - We re-write in standard form :
(x-(-4)²)² + (y - (-22))² = 10²
And now it is easy to identify h and k, h = -4 and k = - 22 and the radius r equal 10. You can now complete the sentence :)
