If x+y=2 and x^2+y^2=2, what is the value of x y ?

Question

GMAT Panda · Accepted Answer

1 We apply the development formula for the square of a sum. (x+y)^2=x^2+y^2+2xy We substitute the known values (x+y)^2=2^2=4 and x^2+y^2=2 into the expansion. 4=2+2xy We isolate the term xy by subtracting 2 from both sides. 4-2=2xy We solve for xy by dividing both sides by 2. 4-2/2=xy

Explanation	Calculations	Help
$We apply the development formula for the square of a sum.$	$(x + y)^{2} = x^{2} + y^{2} + 2 x y$
$We substitute the known values (x + y)^{2} = 2^{2} = 4 and x^{2} + y^{2} = 2 into the expansion.$	$4 = 2 + 2 x y$
$We isolate the term x y by subtracting 2 from both sides.$	$4 - 2 = 2 x y$
$We solve for x y by dividing both sides by 2.$	$\frac{4 - 2}{2} = x y$

Question

Options:

Steps

Final Answer

Question

Options:

Steps

Final Answer

Related questions