# Thread: Factoring an expression with four terms

1. ## Factoring an expression with four terms

x^2-y^2-z^2+2yz
thanks

2. Originally Posted by princess_21
x^2-y^2-z^2+2yz
thanks
$x^2 + xy - xz - xy - y^2 + yz + + zx + yz - z^2$

$= x(x + y - z) - y(x + y - z) + z(x + y - z)$

$=(x + y - z)(x - y + z)$

3. Originally Posted by mr fantastic
$x^2 + xy - xz - xy - y^2 + yz + + zx + yz - z^2$

$= x(x + y - z) - y(x + y - z) + z(x + y - z)$

$=(x + y - z)(x - y + z)$
why did it became like this? x^2 + xy - xz - xy - y^2 + yz + + zx + yz - z^2

i have the same answer but different way. how did you come up with that equation?

here's my solution
x^2-(y^2-2yz+z^2)
x^2-(y-z)^2
{x+(y-z)}{x-(y+z)
(x+y-z)(x-y+z)

4. Originally Posted by princess_21
why did it became like this? x^2 + xy - xz - xy - y^2 + yz + + zx + yz - z^2

i have the same answer but different way. how did you come up with that equation?

here's my solution
x^2-(y^2-2yz+z^2)
x^2-(y-z)^2
{x+(y-z)}{x-(y+z)
(x+y-z)(x-y+z)
Good for you. A much better way. I always do things the hard way.