Question 81337: please check this for me?
7x^2+18-9
x=-b+-sqrt/2a
x=-18+-sqrt/2*7
x=(-18+24)/2*7
x=6/14=3/7
x=-42/14=-3
x=-3,7 Answer by vertciel(183) (Show Source):
You can put this solution on YOUR website! Hello there,
x = 3/7 and x = -3 is correct.
You actually could have solved this question more easily, by factoring the quadratic:
(7x - 3)(x + 3)
Now you can see that x MUST be x = 3/7 and x = - 3.
Also, you could have graphed this quadratic with your calculator to see if your x -intercepts are right.