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# Challenging Problem for you Math Majors

Topic closed. 13 replies. Last post 10 years ago by cps10.

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The Carolinas - Charlotte
United States
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September 12, 2005
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 Posted: July 3, 2006, 1:54 pm - IP Logged

Hey guys/gals:

This is a little off the beaten path of lottery discussion, but I was talking to my nephew last night on the phone and he was telling me about an Algebra problem that he had, and I laughed and said, shoot it to me...after that the laughter subsided and I was going "What on earth?!"

Anyway, I wanted to see who would be able to solve this for me to show that little snot-nosed brat who the man (or woman) is at L.P.

Here it is (and solve using a Matrix showing all steps please...LOL):

Solve for the variables with the equations being:

1. x - 2z = 8

2. 2y + z = -5

3. 3x + y = 5

Let's see how quickly this one gets resolved. LOL

The North Carolina Education Lottery - so much a joke that here are their mascots:

The Carolinas - Charlotte
United States
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September 12, 2005
4138 Posts
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 Posted: July 3, 2006, 2:25 pm - IP Logged

Nobody? LOL...this has taken me a while to figure out as well :)

The North Carolina Education Lottery - so much a joke that here are their mascots:

The Carolinas - Charlotte
United States
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September 12, 2005
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 Posted: July 3, 2006, 3:24 pm - IP Logged

Thanks Derek...do you have a matrix that you used for this?

The North Carolina Education Lottery - so much a joke that here are their mascots:

IL
United States
Member #34578
March 4, 2006
198 Posts
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 Posted: July 3, 2006, 3:26 pm - IP Logged

x = 2

y= -1

z = -3

(sorry had to delete and re type post...)

IL
United States
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March 4, 2006
198 Posts
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 Posted: July 3, 2006, 3:30 pm - IP Logged

kinda no, long to type, not sure if it is correct, uses some shorts, and not follows school standars...

The Carolinas - Charlotte
United States
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September 12, 2005
4138 Posts
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 Posted: July 3, 2006, 3:30 pm - IP Logged

Thanks Derek!

The North Carolina Education Lottery - so much a joke that here are their mascots:

The Carolinas - Charlotte
United States
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September 12, 2005
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 Posted: July 3, 2006, 3:31 pm - IP Logged

Got ya...thanks man!

The North Carolina Education Lottery - so much a joke that here are their mascots:

East of Atlanta
United States
Member #6191
August 11, 2004
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 Posted: July 3, 2006, 3:54 pm - IP Logged

1. x - 2z = 8

8=x-2z
8-x=x-2z-x
negative x cancels out positive x on this side
8-x=2z
(8-x)/2=2z/2
Divide by 2 cancels out the 2 on this side
(8-x)/2=z

----------------------------
2. 2y + z = -5

-5=2y+z
-5-z=2y+z-z
negative z cancels out positive z on this side
-5-z=2y
(-5-z)/2=2y/2
Divide by 2 cancels out the 2 on this side
(-5-z)/2=y

----------------------------
3. 3x + y = 5

5=3x+y
5-y=3x+y-y
negative Y cancels out positive Y on this side
5-y=3x
(5-y)/3=3x/3
Divide by 3 cancels out the 3 on this side
(5-y)/3=x

I believe the above represents what is actually  expected. If dealing with Algebra, basic algebra doesn't care what the value of x, y or z. It cares about how to solve for each. However, if solving for each variable, the answers are

1. x - 2z = 8

x=10
z=1
10-(2*1)=8
10-2=8
8=8

----------------------------
2. 2y + z = -5

y=-1
z=-3
(2*-1)+ -3 = -5
-2 + -3 = -5
-5 = -5

----------------------------
3. 3x + y = 5

x=1
y=2
(3*1)+2=5
3+2=5
5=5

The Carolinas - Charlotte
United States
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September 12, 2005
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 Posted: July 3, 2006, 3:57 pm - IP Logged

Thanks Sir Metro!

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FEMA Region V Camp #21
United States
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July 27, 2002
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 Posted: July 3, 2006, 4:23 pm - IP Logged

...and they say you gotta be stupid for playing the lottery.

LP amazes me at how false that assumption is.

Posted 4/6:  IL Pick 3 midday and evening until they hit:  555, 347 (str8).

The Carolinas - Charlotte
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 Posted: July 3, 2006, 4:35 pm - IP Logged

Rick

There are so many freakishly intelligent people on this Board...I love it!

The North Carolina Education Lottery - so much a joke that here are their mascots:

Michigan
United States
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September 24, 2005
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 Posted: July 3, 2006, 4:47 pm - IP Logged

X= my bankroll before lottery purchases.
Y and Z = my bankroll at various stages of checking for winners.

IL
United States
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March 4, 2006
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 Posted: July 3, 2006, 5:14 pm - IP Logged

/  x-2z=8
|
{  2y+z=-5
|
\  3x+y=5

/  x-2z=8
|
z=-5-2y
|
\  3x+y=5

/  x-2(-5-2y) = 8
{
\  3x+y=5

/  x-2(-5-2y) = 8
{
\  y=5-3x

{  x-2[-5-2(5-3x)]=8

{  x-2(-5-10+6x)=8

{  x+10+20-12x=8

{  x-12x+30 = 8

{  -11x = 8-30

{  -11x = -22

{  x = -22 / -11

{  x = 2

From the green line
y = 5-3x (x = 2, so:)

y = 5-6

y = -1

From the red line:

z=-5-2y (y = -1, so:)

z=-5+2

z = -3

Hopefully no typos/erros here.

The Carolinas - Charlotte
United States
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September 12, 2005
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 Posted: July 3, 2006, 5:39 pm - IP Logged

Thank you all!!!

The North Carolina Education Lottery - so much a joke that here are their mascots:

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