Question

need help with a problem, in comments:

Answer 1

help me find x please! \[2x^2-8=10\]

Answer 2

X=3?

Answer 3

how?

Answer 4

x=3.01

Answer 5

You take -8 to the rhs(right hand side) and then you divide 18 with 2 and then square root 9 to get 3.

Answer 6

where'd you get the 9 from?

Answer 7

@GoldPhenoix little help here please gold? Would mean alot

Answer 8

So you have an equation: 2x^2 - 8 = 10.
What is 2x^2 give you?
Well another way of writing it is: 2x * 2x. That would give us 4x^2.
So your equation should look like: 4x^2 - 8 = 10
To find x, you want to get rid of -8.
To get rid of -8, you want to add 8 to both side
-8 + 8 = 0 (Cancel out)
10 + 8 = 18
So your equation should look like: 4x^2 = 18
Now, what do we do next? There's many way.
Hold on for a moment.

Answer 9

\[x=9\] perhaps?

Answer 10

Arg. I forgot how to do it. Sorry. =/

Answer 11

But it's definitely not 9.

Answer 12

ffs. What do you do to the \[4x^2\] to get rid of that exponent then?

Answer 13

I remember now. So you have:
4x^2 = 18
You want to do reverse PEMDAS to find x, right?
So you divide both side by 4.

4x^2 / 4 = x^2
18 / 4 = 4.5

So now your equation should look like: 4.5 = x^2

Answer 14

To get rid of ^2, you want to square root both side.

Answer 15

\[2x^2 -8 =10\\+8~both~sides~ 2x^2 =18\\divide~both~side~by~2~you~got ~x^2 = 9\\squareroot~both~sides~x=3~and~x=-3\]

Answer 16

^ is the way i was trying to explain

Answer 17

no x=4 if use the qudnomial theory and apply is alongside with tan

Answer 18

Ooh. My bad. T~T

Answer 19

ok