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#1 2016-01-29 05:44:33

Mathegocart
Member
Registered: 2012-04-29
Posts: 2,226

Urgent system of linear equations

Help, I keep getting negative results
A father is 32 years older than his son. In 4 years, the father will be 5 years older than his son. How old is each now?
I have made these
y=x+32
y+4=5(x+36)
in 4 years
y= fathers age
x=sons age?
Can someone help me?


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#2 2016-01-29 06:07:07

Nehushtan
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Registered: 2013-03-09
Posts: 957

Re: Urgent system of linear equations

mathgogocart wrote:

y=x+32
y+4=5(x+4)


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#3 2016-01-29 06:34:23

Mathegocart
Member
Registered: 2012-04-29
Posts: 2,226

Re: Urgent system of linear equations

Nehushtan wrote:
mathgogocart wrote:

y=x+32
y+4=5(x+4)

Shouldn't it be 36 because 32+4 years is 36?
Sorry if I seem kinda brushed up on this.


The integral of hope is reality.
May bobbym have a wonderful time in the pearly gates of heaven.
He will be sorely missed.

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#4 2016-01-29 07:14:22

Nehushtan
Member
Registered: 2013-03-09
Posts: 957

Re: Urgent system of linear equations

In 4 years' time his son will be x+4 years old, not  x+36 years old.


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#5 2016-01-29 09:34:10

math9maniac
Member
From: Tema
Registered: 2015-03-30
Posts: 443

Re: Urgent system of linear equations

From the above interpretation, shouldn't the wording of the question be: "In 4 years, the father will be 5 times as old as his son" ? Since the idea of "5 years older in 4 years, gives an impossible solution?


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#6 2016-01-29 10:47:18

Nehushtan
Member
Registered: 2013-03-09
Posts: 957

Re: Urgent system of linear equations

http://www.algebra.com/algebra/homework … 25045.html

Last edited by Nehushtan (2016-01-29 10:58:54)


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#7 2016-01-29 10:52:36

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Urgent system of linear equations

Hi mathgogocart;

You have not copied the problem correctly. This did not deter Nehushtan from getting the correct answer but I am stating it here for the record.

A father is 32 years older than his son. In 4 years the father will be 5 times as old as his son. How old is each now?


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