Question

Can anyone help me?

Answer 1

with what?

Answer 2

That one

Answer 3

we just started learning this

Answer 4

I'm having troubles with it. I know b<0, but not a

Answer 5

Oh ,, I posted the wrong question

Answer 6

There you are~

Answer 7

Though, the previous one is also the question I don't know. Just do it later.

Answer 8

if x was zero then b would be........

Answer 9

I told you I know b<0. I don't know range of value for a only

Answer 10

a has to be postive

Answer 11

why?

Answer 12

we know b is negative ...

x is postive /...... x^2 is postive ......-x^2 is negative...

so we have two negative terms but still ax is reaching above the x axis...
we x is postive ..... so a must be postive to make ax postive

plus ax has to be greater than -x^2+b

Answer 13

OMG, I've never though in that way. Thank you!

Answer 14

cool
but b could be so large like -1000000 that it would never go above the line