Question

im lost in how to do this

Answer 1

this is it

Answer 2

Wow i dont know how to do that sorry lol :O

Answer 3

its all good

Answer 4

i just am really lost

Answer 5

i wish i would help you .sorry

Answer 6

First write
\(f(x) = x^2 - 81\)

Then let \(y = f(x)\):
\(y = x^2 - 81\)

Next, swap \(x\) and \(y\)
\(x = y^2 - 81\)

Afterwards, isolate \(y\).

@Player_2 Would you like to try isolating y?

Answer 7

ill try

Answer 8

u square root y^2?

Answer 9

then i get lost

Answer 10

x=y^2 - 81

I would first add +81 to both sides , as the next step. what do you get?

Answer 11

81x=y^2

Answer 12

like this
x+81 = y^2 - 81+81

Answer 13

on the right side you have -81+81 and that simplifies to 0
and y^2 +0 is y^2
so you now have
x+81= y^2
or
y^2 = x+81

now you can "take the square root" of both sides

Answer 14

im a bit confused what to do 81x

Answer 15

there is no 81x
what do you mean ?

Answer 16

x+81