# SOLVING INEQUALITIES USING INTERVAL NOTATION

This week in math we learned about how to solve inequalities and using interval notation.

So to start off as a reminder from grade 9, an inequality is similar to an equation except for that it has a greater than or less than or equal to sign. But now in precalculus 11 we are solving either quadratic or linear inequalities. An easier way of undersranding a linear inequality especially when it is put on a graph is to graph both sides of the inequality ex: say we have the linear inequality of $2x+6 \geq 4$ in this inequality it is asking us where the Line $2x+6$ is greater than or ABOVE the line $y=4$ so on a graph we would put both lines down and since it is asking for greater than or equal to normally we would write $x \geq -1$ since that is where they intersect. But with the addition of Interval notation we now need to add that it goes all the say to infinity. Meaning that the answer would look like this: $[-1, \infty )$ where the square bracket indicates that the number is included and the round bracket means either not included or when there is an infinity sign, it would mean undefined.