Graphing an inequality on a number line, is very similar to graphing a number. For instance, look at the top number line x = 3. We just put a little dot where the '3' is, right?
Now an inequality uses a greater than, less than symbol, and all that we have to do to graph an inequality is find the the number, '3' in this case and color in everything above or below it.
Just remember
if the symbol is (≥ or ≤) then you fill in the dot, like the top two examples in the graph below
if the symbol is (> or
The greatest common factor, or GCF, is the greatest factor that divides two numbers. To find the GCF of two numbers: List the prime factors of each number. Multiply those factors both numbers have in common. If there are no common prime factors, the GCF is 1.
The least common multiple (LCM) of 2 numbers is the smallest number that they both divide evenly into. One good way to find the least common multiple of 2 numbers is to multiply both numbers by 1,2,3,4,5... and then find the first multiple that appears in both lists.
Where a number is written in two parts:
First: just the digits (with the decimal point placed after the first digit),
Followed by: ×10 to a power that will put the decimal point back where it should be.
The rules that say which calculation comes first in an expression
They are:
• do everything inside parentheses first: ()
• then do exponents, like x2
• then do multiplies and divides from left to right
• then do the adds and subtracts from left to right
To find the mean, add up the values in the data set and then divide by the number of values that you added. To find the median, list the values of the data set in numerical order and identify which value appears in the middle of the list. To find the mode, identify which value in the data set occurs most often.
By “simplifying” an algebraic expression, we mean writing it in the most compact or efficient manner, without changing the value of the expression. This mainly involves collecting like terms, which means that we add together anything that can be added together. The rule here is that only like terms can be added together.
Examples:
3x, x, and –2x are like terms.
2x2, –5x2, and are like terms.
xy2, 3y2 x, and 3xy2 are like terms.
xy2 and x2 y are NOT like terms, because the same variable is not raised to the same power.