click to play button
click to replay button
2-5-19
X
    00:00 / 00:00
    CC
    On this problem, we need to know the leading coefficient and the constant. So all the possible rational roots are all the possible factors of the constant divided by the possible factors of the leading coefficient. So in this case we get positive -1, positive -2, positive -3 positive -6. We're going to do some some synthetic division. So I used one and got a remainder of -30. So I know that that point is one negative 30I then used three and got three negative 78. I used six and I got out six zeros. So I know that six is a root. When I factor out that X - 6 then I get left the X ^2 + 6 X -1 and that came from right here X ^2 + 6 X -1. Now that doesn't factor so I have to use quadratic formula opposite b ± b ^2 - 4 * a * C all over 2A. Simplifying that down we get the -3 ± sqrt 10. So our 3 answers are six -3 plus root 10 and -3 minus root 10.