00:02
We're going to solve the equation negative x squared plus x minus 1 equals 0 by completing the square.
00:08
The first thing we're going to do is divide by negative 1 to make the x squared positive.
00:14
So i'm going to divide every term by negative 1 and we get x squared minus x plus 1 equals 0.
00:23
I'm then going to subtract 1 from both sides.
00:27
We get x squared minus x equals negative 1.
00:30
We're going to take half of the b value.
00:34
So this is my a, my b, and my c.
00:37
So in this equation, a equals 1, b equals 1, b equals negative 1, and c equals.
00:49
So we're going to take half of the b value, which is that negative 1.
00:54
So we'll get negative 1 half, and we're going to square it.
00:59
Negative 1 .5 squared is 1 4th...