Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

You are not logged in.

#1 2013-02-10 05:01:58

cooljackiec
Member
Registered: 2012-12-13
Posts: 185

x =

Find all real values of  x that satisfy the equation (x^2-82)^2 = 324

Last edited by bobbym (2013-02-10 06:04:17)

I see you have graph paper.
You must be plotting something

Offline

#2 2013-02-10 05:55:53

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,115

Re: x =

Hi;

x  = 10, x = 8, x = -8, x = -10

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#3 2013-02-10 07:59:25

cooljackiec
Member
Registered: 2012-12-13
Posts: 185

Re: x =

help me on another one

\frac{c}{c-5}=\frac{4}{c-4}

FInd c.

Also, the LaTeX doesn't seem to work..

I see you have graph paper.
You must be plotting something

Offline

#4 2013-02-10 08:02:06

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,115

Re: x =

Hi;

Latex is out temporarily.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#5 2013-02-10 17:49:24

Sabbir
Guest

Re: x =

If you cross multiply,then you'd get c^2-4c=4c-20 which is c^2-8c+20=0,now you just have to find the polynomial's roots.

#6 2013-02-10 23:20:14

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,115

Re: x =

Hi;

I am getting

c = 4 - 2 i and c = 4 + 2 i

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline