Answer:
85
Step-by-step explanation:
The 9 th square number is 9² = 81
The 2 nd square number is 2² = 4
sum = 81 + 4 = 85
Answer:
x is less then or equal to -3
x<-3 (the < has to have a line underneath)
Step-by-step explanation:
Answer:

Step-by-step explanation:
<u>Equation of a Circle</u>
A circle of radius r and centered on the point (h,k) can be expressed by the equation

We are given the equation of a circle as

Note we have corrected it by adding the square to the y. Simplify by 3

Complete squares and rearrange:



We can see that, if r=4, then

Or, equivalently

There are two solutions for
:

Keeping the positive solution, as required:

Answer: 2 × 3 × 3 or we can also write them as 2 × 32, where 2 and 3 both are prime numbers.
Answer:
0.173 probability that she gets exactly three questions correct.
Step-by-step explanation:
For each question, there are only two possible outcomes. Either she guesses the correct answer, or she does not. The probability of guessing the correct answer for a question is independent of other questions. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
Seven questions:
This means that 
Each question has four choices.
Abby guesses, which means that 
Find the probability to the nearest thousandth, that Abby gets exactly three questions correct.
This is P(X = 3).

