help!

We can make $x^2 - y^2 = -12$ into $(x-y)(x+y) = -12$ by using “Difference of Squares”. Since we know that $x+y = 6$, we can substitute that in. Now we have $6(x-y) = -12$. We can divide $6$ on both sides, which gives us $x - y = -2$. We also still have the equation $x + y = 6$. We can use elimination to get rid of $x$. We will subtract the second equation from the first. This gives us $-2y = -8$, so $y = 4$. We can plug this back into any equation to get $x$. So $y = 4$ and $x = 2$.

- Daisy

Thanks, Daisy !!!.....Just wanted to try this one , too....I like these kinds of problems ....

x^2  - y^2  = -12   and    x +  y  = 6   (1)

(x + y) ( x - y)  =  -12

6 ( x - y)  = -12

x - y  =  -2      (2)

Add (1)   and (2)   and we have that   2x  = 4  ⇒   x  = 2

And y =  2 + y  = 6   ⇒  y  = 4

So  (x ,y)  = ( 2, 4)