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

You are not logged in.

#1 2005-03-21 22:49:12

I.M Stuck
Guest

Algebra

what is x when:

3(x+456)+5(56x-45)=0

#2 2005-03-21 23:43:57

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,552

Re: Algebra

Was this set by a teacher, or are you just curious?

3(x+456)+5(56x-45)=0

Multiply out: 3x+3 * 456 + 5 * 56x + 5 *(-45)=0   (i am using * to mean multiply, so it doesn't look like x)

Simplify: 3x + 1368 + 280x -225 = 0
Simplify More: 283x + 1143 = 0

Rearrange (subtract 1143 from both sides): 283x = -1143
Rearrange (divide both sides by 283): x = -1143/283

So, x = -1143/283 = -4.04


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

Offline

#3 2005-03-22 08:18:13

Roraborealis
Member
Registered: 2005-03-17
Posts: 1,594

Re: Algebra

HAHAHAHAHAHAAHA! I.M. Stuck! That's funny!


School is practice for the future. Practice makes perfect. But - nobody's perfect, so why practice?

Offline

#4 2005-04-12 03:48:45

Mr T
Member
Registered: 2005-03-30
Posts: 1,012

Re: Algebra

i pity the foo' who messes wiv mi homie


I come back stronger than a powered-up Pac-Man big_smile
I bought a large popcorn @ the cinema the other day, it was pretty big...some might even say it was "large
cool Fatboy Slim is a Legend cool

Offline

#5 2005-04-13 08:45:50

mohit
Member
Registered: 2005-04-13
Posts: 7

Re: Algebra

I.M Stuck wrote:

what is x when:

3(x+456)+5(56x-45)=0

3x+1368+280x-225=0
283x+1143=0
283x=-1143
x=-1143/283
therefore x= -4.04

Offline

Board footer

Powered by FluxBB