Tutor profile: Natalie A.
Compare and contrast Permutations versus Combinations.
Both are used when finding the number of possibilities when choosing items from a group where no item can be repeated. Permutations are when the order matters and combinations are when the order does not matter.
In the expression 2x + 4, why is 2x called the variable term and 4 is called the constant term?
Let's say x = 1. 2x = 2 and 4 = 4. Let's say x = 2. 2x = 4 and 4 = 4. Show a few more of these examples. Explain the variable term VARIES as x changes. The 4 term stays CONSTANT regardless of the value of x.
In order to show the difference between a solution to a one-variable linear equation and two-variable linear equation: What is the solution to x + 2 = 12? Why? What is the solution to x + y = 12? Can you list all of them?
x=10 because that is the number that works when we plug it into the equation. (2, 10), (3, 9), (4, 8), etc. We cannot list all of them because there are infinite. This would lead into the discussion of why graphs are necessary (as a graphical representation of infinite solutions, in part).