+2448 Need help with a couple, also please correct me if i'm wrong
3. x=3y+2
-2 from both sides= x-2=3y
(3)x-2(3)=(3)3y=
y=3x-6
4. x=2/3y-5
+5 both sides
x+5=2/3y
(3/2)x+(3/2)5=(3/2)2/3y=
y=3/2x+7.5
5. x=y^2+8
-8 from both sides= x-8=y^2 (not sure what comes next) is it x-8^2=(y^2)^2 ???
6. x=(y+3)^2
Not sure what to do next for this one but I tried a little bit: x^2=((y+3)^2)^2=x^2=y+3 I don't know >.<
+128474 3. f(x) = 3x + 2
Here's the way I learned it..... for f(x), write "y".... get x by itself... "swap" x and y
and for "y" write f-1(x) [this notation represents the inverse ]
So we have
y = 3x+ 2
y - 2 = 3x
[y - 2] / 3 = x "swap" x and y
[x - 2 ] / 3 = y
[x -2 ] / 3 = f-1(x)
BTW....swapping x and y like you did in your first step is OK, too.....!!
#4 looks good...!!!
Here's the last two
f(x) = x^2 + 8
y = x^2 + 8
y - 8 = x^2 take both roots
±√ [y -8] = x swap x and y
±√[ x - 8 ] = y
±√[x - 8] = f-1(x)
f(x) = (x + 3)^2
y = (x + 3)^2 take both roots
±√y = x + 3
±√y - 3 = x swap x and y
±√x - 3 = y
±√x - 3 = f-1(x)
+2448 Thank you, that's not quite how I learned it but maybe i'll get used to it being that way...
