# Math Help

Discussion in 'Members' Lounge' started by reckedracing, Feb 17, 2010.

1. ### reckedracingTTIWWOPVIP

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I forgot my old school math.
Someone throw me a bone on this one.
Would prefer to see it worked out.

A+B=65
A3+B2=179

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A + B = 65
3*A + 2*B = 179

A = 65-B

substitute

(65-B)*3 + 2*B = 179
195 - 3*B + 2*B = 179
195 - B = 179
B = 16

substitute again

A = 65-16
A = 49

Easy

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3. ### CRX-YEMSuper ModeratorModeratorVIP

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Could be done via matrices with cramers rule as well imho is a lot easier than the substitution method.

4. ### reckedracingTTIWWOPVIP

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ahhhh
it was always the end that screwed me
my second equation i solved A = 49 but then when i ran it back through i divided by 2 twice and ended up with
147+B2=179
B=8

the first and third time i ended up with
195-B3+B2=179
195-B5=179
-B5 = 16
B = 3.2

I thought I was making my beginning formulas wrong.
A farmer has three legged cows and chicken.
There are 65 heads and 179 legs.
How many cows does the farmer have.

Is this the other method you were refering to CRXYEM

Last edited: Feb 17, 2010

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