Question

please help
express in interval notation
x≥7
a. (-oo,7)
b. [7,oo)
c. (-oo,7]
d. (7,oo)

Answer 1

"oo" Means ?

Answer 2

that means x is greater or equal to 7, so it could be 7 to infinity

Answer 3

i don't understand this

Answer 4

"oo" is infinity.
If you have an equal with your > or <, you want to use a "["
If you don't have an equal with your > or <, you want to use a "("

Answer 5

Let's draw the area represented by x>=7 on a number line

Answer 6

Your left boundary is 7...and there's an equal...so use "[" on the left
Your right boundary is infinity. Always use a ) or ( with infinity...never a [ or ]

Answer 7

okay i think i understand it now