x^2 - 8 > 0
x^2 > 8
That should help.
Find all real numbers x such that x^2 -8>0. Write your final answer in interval notation.
I really just need a starter step. I remember these questions, but I'm not sure how to start. Please help!
3 answers
So the sign is flipped because we moved a negative number, right?
no, you can add and subtract anything without flipping the direction. Only if you multiply or divide by a negative value does the direction change.
It's really just a shortcut to moving things to the other side:
-2x < 8
0 < 8+2x
-8 < 2x
-4 < x
That's the same as dividing and flipping at once:
-2x < 8
x > -4
It's really just a shortcut to moving things to the other side:
-2x < 8
0 < 8+2x
-8 < 2x
-4 < x
That's the same as dividing and flipping at once:
-2x < 8
x > -4
1 answer