When the lines are parallel then there is no solution to the system of equations.
This happens because the intersection is the solution. And when there is no intersection then there is no solution.
The answer is

.
Before we rationalize the denominator, we must simplify the numerator and denominator. We evaluate the square root on the top, and combine like terms on the bottom:

To rationalize the denominator, we multiply by the conjugate. The conjugate is found by making the imaginary term of the complex number, the i part, the opposite sign. The conjugate of -2-i is -2+i:
Answer:
b. A binomial variable with 25 independent trials
Step-by-step explanation:
The conducted experiment is binomial experiment because outcome can be divided into success or failure. The success would be the people who read novel in the past year and also responses are independent of each other. We have to find the number of trials n in the given problem.
we are given that variance of R=6 and p=probability of success=0.4.
We know that variance of binomial distribution is
Variance=npq
where q=1-p=1-0.4=0.6.
By putting the values in variance formula, we can get the value of n.
6=n*0.4*0.6
6=0.24*n
n=6/0.24
n=25
Hence, random variable R is a binomial variable with 25 independent trials.
I believe this is the distributive property.