sandy wrote:

If \(x - y = \frac{1}{2}\) and \(x^2 - y^2 = 3\), what is the value of x + y?

We can also solve this by first recognizing that x² - y² is a

difference of squaresWe know that x² - y² = (x + y)(x - y)

Given: x² - y² = 3

Factor to get: (

x + y)(

x - y) = 3

We're also told that

x - y = 1/2So, we can now say: (

x + y)(

1/2) = 3

From this, we know that

x + y = 6Answer: 6

Cheers,

Brent

_________________

Brent Hanneson – Creator of greenlighttestprep.com

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