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Existential

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my apologies for the easy question, but ive got conflicting solutions for this one so i just thought id check here.

Solve 4x+3y=11 and 3x+y=2 simultaneously.

(full working plz)
 

SpiralFlex

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Call this Equation 1

Call this Equation 2

Equation 2 * 3

Call this Equation 3

Equation 3 - Equation 1







Sub in for y.

 
Last edited:

elbatiolpxeho

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Full working:

4x+3y=11 ---(1)
3x+y=2 ---(2)

-----

from (2):
y=2-3x ---(3)

subs. (3) into (1):
4x+3(2-3x)=11
4x+6-9x=11
-5x=5
x=-1 ---(4)

subs. (4) into (3):
y=2-3(-1)
y=5
 

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