6*7=42
It’s the answer I guess.
Use the formula 0 = b^2-4ac
0 = -b^2-4(2)(-9)
0 = -b^2+72
b^2 = 72
b = square root of 72
b = 2 real numbers
It is given the probability that a dancer like ballet is 0.35
So, P(B) = 0.35
It is given the probability that a dancer like tap is 0.45
So, P(T)= 0.45
The probability that he likes both ballet and tap is 0.30
So, 
the probability that the dancer likes ballet if we know she likes tap. This is the case of conditional probability.
So, 

= 0.666
= 0.67
Therefore, the probability that the dancer likes ballet if we know she likes tap is 0.67.
Option 3 is the correct answer.
each term is negative and 1/4 of previous term so the nth term is the n-1 term times -1/4 so f(n)= -1/4 f(n-1)
You are correct, it would be a reflection across the y-axis. I am great at visualizing but for those who are not (Not saying you) all they have to do is cut out a parallelogram and mimic the movements.