Hi folks! This is a seemingly-easy question, but the way the O.G. solves for "x" is different than I understood it to be...
Their process:
2x^2 = 400
x^2 = 200
etc.
Why do we not take the sq. root of the 400 first, to be left with 2x = sq.root(400)? I'm using PEMDAS to problem solve; why does that order not apply here?
Thanks so much in advance!
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ostrowskiamy
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Anju@Gurome
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It is given that 2x^2 = 400 NOT (2x)^2 = 400ostrowskiamy wrote:Why do we not take the sq. root of the 400 first, to be left with 2x = sq.root(400)? I'm using PEMDAS to problem solve; why does that order not apply here?
Hence, if you take square root first it'll be (√2)x = √400 = 20
Hope that helps.
Anju Agarwal
Quant Expert, Gurome
Backup Methods : General guide on plugging, estimation etc.
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Quant Expert, Gurome
Backup Methods : General guide on plugging, estimation etc.
Wavy Curve Method : Solving complex inequalities in a matter of seconds.
§ GMAT with Gurome § Admissions with Gurome § Career Advising with Gurome §
