Three equations, three unknowns
Maths and statistics discussion, revision, exam and homework help.
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Three equations, three unknownsx+3y=2
-2x+3y+z=-1
y+z=-1
z=-1-y
x=2-3y
-2(2-3y)+3y+(-1-y)=-1
8y-5=-1
y=2
z=-1-2
z=-3
x=2-3(2)
x=-4
Can anyone see where I have gone wrong as my answers do not match the equations if plugged back in.Last edited by Gorrilaz; 07-05-2012 at 01:18. -
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Re: Three equations, three unknownsNo sorry it was actually-4+6y+3y-1-y=-1(Original post by FloydHead)
You messed up here.
When you multiply out the brackets, you should have gotten:
-4 + 6y + 3y + 1 - y = -1
which simplifies to
8y - 3 = -1
As z=-1 -y I just write that part wrong. -
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Re: Three equations, three unknownsThe equations after the first 3 are working out, they're just rearranged to make x and z in terms of y.(Original post by AtomSmasher)
Unless I'm badly mistaken, you can find all 3 variables from the first 3 equations given. Or is this one of those questions where you have to do it a given way?
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Re: Three equations, three unknownsy=0.5 i did it wrong lol(Original post by fire sale)
I've been trying this another way but I just can't get to y = 2. Even when I put y = 2 to get x and z I get values that don't work out. Where am I going wrong?! Are y'all sure these equations are self consistent?????
