How do you solve #x^2 = x + 2 #?

1 Answer
Jun 26, 2016

#x= 2 or x=-1#

Explanation:

It is a quadratic equation, so make it equal to 0.

#x^2 -x -2 = 0 " factorise"#

Find factors of 2 which subtract to give 1.
As 2 is a prime number it only has factors 2 and 1.

The signs will be different, there must be more negatives.

#(x-2)(x+1)=0#

If #x-2 = 0#, then x = 2
If #x+1 = 0#, then x = -1