A biased example: Asking students who are in line to buy lunch
An unbiased example: Asking students who are leaving/going to lunch(<em>NOT buying </em><em>lunch</em><em />).
But in this case, the answer choices can be... confusing.
Don't panic! You're given numbers and, of course, your use of logic.
Answer choice A: 100 students grades 6-8
Answer choice B: 20-30 students any <em>one</em> grade<em></em><em>
</em>Answer choice C: 5 students
<em></em>Answer choice D: 50 students grade 8
An unbiased example would be to choose students from <em>any grade.</em> So we can eliminate choices B and D.
Now, the question wants to <em>estimate how many people at your middle school buy lunch.</em> This includes the whole entire school, and if you are going to be asking people, you aren't just going to assume that if 5 people out of 5 people you asked bought lunch, the whole school buys lunch.
So, to eliminate all bias and/or error by prediction, answer choice A, the most number of students, is your answer.
This can be solved by factoring.
First, set the expression equal to zero.

Then, find two the factors of

whose sum is

.

Split

into these two factors.

Next, factor by grouping.

By the Zero Product Property, set each factor equal to zero.


These are the solutions. The Complex Conjugate Root Theorem and the Fundamental Theorem of Algebra both state that, in essence, real and imaginary solutions come in pairs of two and every polynomial of degree

has exactly

complex roots, but real roots are also complex roots. That sounds confusing, but this just means that you're done.
Your answers are -2 and 1/3. There are two real roots.
Answer:
180,45
Step-by-step explanation:
The number of monthly payments Brenda will have will be given by:
Number of payments=[Number of years]×[number of months]
Number of years=5
Number of months=12
hence
# Payments=5*12=60 monthly payments