Question

if x+yand xy=4find x-y using identities
​

Answer 1

$x + y = 4 \\ \\ xy = 4 \\ \\ = > (x - y) {}^{2} = (x + y) {}^{2} - 4xy \\ \\ = > (x - y) {}^{2} = 4 {}^{2} - 4 \times 4 \\ \\ = > (x - y) {}^{2} = 16 - 16 \\ \\ = > (x - y) {}^{2} = 0 \\ \\ = > x - y = 0.$

I hope this helps.

Answer 2

Answer:

don't know ok........