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If x – y = and x2 – y2 = 3, what is the value of x + y?
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23 Jun 2018, 11:50
23 Jun 2018, 11:50
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98% (00:33) correct
1% (01:52) wrong based on 61 sessions
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Re: If x – y = and x2 – y2 = 3, what is the value of x + y?
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28 Jul 2018, 16:09
28 Jul 2018, 16:09
Expert Reply
Explanation
The Difference of Squares (one of the “special products” you need to memorize for the exam) is \(x^2 - y^2 = (x + y)(x - y)\).
Write this pattern on your paper and plug in the given values, solving for x + y:
\(x^2 - y^2 = (x + y)(x - y)\)
\(3 = (x + y)(\frac{1}{2})\)
\(6 = x + y\)
The Difference of Squares (one of the “special products” you need to memorize for the exam) is \(x^2 - y^2 = (x + y)(x - y)\).
Write this pattern on your paper and plug in the given values, solving for x + y:
\(x^2 - y^2 = (x + y)(x - y)\)
\(3 = (x + y)(\frac{1}{2})\)
\(6 = x + y\)
