x 2 + y 2 + a x + b y = c
x2 + y2 − 2x + 6y − 6 = 0
Steps:
x^2 + y^2 - 2x + 6y - 6 = 0
(x - 1)^2 + (y - (-3)^2=4^2
Which means...
Center = (1,-3)
Radius = 4
Or option B
I just answered this xD
1-3 is given as an example.
4. True
5. False. It is the same thing twice
6. True
We'll start by calling the number of pigeons we started with x, because it's the unknown.
After she clapped 1/3 flew away so she was left with
(1 - 1/3) x = (2/3) x
Two flew back, so now there are
(2/3) x + 2
She clapped again and half left, half stayed, so now
(1/2) ( (2/3) x + 2 )
One came back and there were five,
(1/2) ( (2/3) x + 2 ) + 1 = 5
Solving is unraveling.
(1/2) ( (2/3) x + 2 ) = 4
(2/3) x + 2 = 8
(2/3) x = 6
x = (3/2) 6 = 9
Answer: 9 pigeons
Check: Reviewing the story, 9 -> 6 -> 8 -> 4 -> 5 good
You use the equation Ax^2 + Bx + C to solve this equation.
The answer is 25.
I hope this helps :D
Note that all of these choices but the last have 1-number responses. The last choice involves collecting data: the ages of the concert attendees. So only the last pertains to statistics.
