Find x

**jkami** · February 27th 2009, 06:02 PM

Find $-x^2$ when x=2

Is it 4 or -4?

**mr fantastic** · February 27th 2009, 07:22 PM

Originally Posted by jkami

Find $-x^2$ when x=2

Is it 4 or -4?

Are you asked to find (-x)^2 or -(x^2)? Which of these do you think -x^2 would mean?

**manjohn12** · February 27th 2009, 07:22 PM

Originally Posted by jkami

Find $-x^2$ when x=2

Is it 4 or -4?

$-x^2 = -(x^2)$ by associative law. Thus we have $-(2^2) = -4$ .

**DengXiang** · February 27th 2009, 08:00 PM

Originally Posted by jkami

Find $-x^2$ when x=2

Is it 4 or -4?

Initially,do the $2^2$ ,which equates to 4.
Thereupon,you can espy that $-x$ is a negative one.

Thereby, ultimately you compute $,-x$ times 4= -4

Thread: Find x