What is the equation of a circle with center (9,-7) and radius 2?
A. (X - 9)2 + (y + 7)2 = 2
B. (X-9)2 + ( + 7)2 = 4
C. (x + 9)2 + (y - 7)2 = 2
D. (x + 9)2 + (x - 7)2 = 4

B. (x-9)^2 + (y + 7)^2 = 4

Step-by-step explanation:

The standard form of a circle is (x-h)^2 + (y-k)^2 = r^2. Hopefully you can memorize that, because it's very helpful in these problems!

(h,k) is our center, and r is our radius, so plug those values into the standard form:

(x - 9)^2 + (y + 7)2 = 2^2

2^2 = 4, so

B. (x - 9)^2 + (y + 7)2 = 4 is our answer!

the aswere is the one with all 8's and the second one is with the 10,8 and 6

step-by-step explanation:

85.560%

step-by-step explanation:

conditional probability is defined as:

p(a|b) = p(a∩b) / p(b)

in other words, the probability that a occurs, given that b has occurred = the probability that both a and b occur / the probability that b occurs.

in this example:

p(turns 64 | turns 44) = p(turns 64 & turns 44) / p(turns 44).

if someone turns 64, they must have already turned 44, so:

p(turns 64 | turns 44) = p(turns 64) / p(turns 44)

on page 42, we see that of the original 100,000, 94944 turn 44, and 81234 turn 64.   therefore:

p(turns 64 | turns 44) = 81234 / 94944

p(turns 64 | turns 44) = 0.85560