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samark
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D it is,
If there are x2 and x terms - remember to look for equations that are reverse FOIL. :)
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Supasubi,

"If there are x2 and x terms - remember to look for equations that are reverse FOIL."

Can u pls elaborate your method as how u test whether any equation is a reverse FOIL?

Thanks!
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samark
Supasubi,

"If there are x2 and x terms - remember to look for equations that are reverse FOIL."

Can u pls elaborate your method as how u test whether any equation is a reverse FOIL?

Thanks!

Same question here...
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There is no "test" per say. Its just patter matching. If you can see an expression which has a A^2 and an A term where A is an algebraic expression, you can solve it like a quadratic.

Eg. Consider the expression : \(4x^2+4y^2+x+32=y(1+8x)\)
The way I'd change that around is \(4(x^2+y^2-2xy) + (x-y) + 32 =0\)
OR \(4(x-y)^2+(x-y)+32=0\)

So its really just looking out for things, rather than some objective criterion you can apply
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Thanks shrouded1! very nicely explained.. :)
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x, y---+ve nos

we get xy(xy+3)=18.....if xy=3 the equation makes sense....substitute x=3 and y=1 considering options are in y it'll be easier to calculate....d) gives us 9 for y=1
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OPEN DISCUSSION OF THIS QUESTION IS HERE: if-x-and-y-are-positive-and-x-2y-2-18-3xy-then-x-140728.html

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