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If (x + y)^2= 16 and (x– y)^2= 9 , what is one possible.....
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06 Oct 2020, 09:08
06 Oct 2020, 09:08
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Question Stats:
66% (00:41) correct
33% (01:50) wrong based on 9 sessions
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If (x + y)^2= 16 and (x – y)^2= 9 , what is one possible value of (x^2-y^2) ?
Re: If (x + y)^2= 16 and (x– y)^2= 9 , what is one possible.....
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06 Oct 2020, 19:55
06 Oct 2020, 19:55
x+y=|4|
x-y=|3|
\(x^2-y^2 =(x+y)(x-y)\)
\(x^2-y^2=|12|\)
it can be +12 ,-12
x-y=|3|
\(x^2-y^2 =(x+y)(x-y)\)
\(x^2-y^2=|12|\)
it can be +12 ,-12
Re: If (x + y)^2= 16 and (x– y)^2= 9 , what is one possible.....
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06 Sep 2021, 12:14
06 Sep 2021, 12:14
1
It is a very easy question, I first approached it incorrectly, but after wasting 1 minute on it, thought of the best approach.
Given, (x + y)^2= 16 and (x – y)^2= 9
Take square roots on both sides of the equation.
x+y = +- 4
x-y = +- 3
So possible values of (x^2-y^2) = (+-4) * (+-3) = +-12
Given, (x + y)^2= 16 and (x – y)^2= 9
Take square roots on both sides of the equation.
x+y = +- 4
x-y = +- 3
So possible values of (x^2-y^2) = (+-4) * (+-3) = +-12
