Question

Using the discriminant, determine the number of real solutions.
-2x^2+x-28=0

Answer 1

I hope this cleared your doubt!

Answer 2

Discriminant: b² - 4ac
Equation: y = -2x² + x - 28
a = -2
b = 1
c = -28
1² - (4*-2*28) = 225
-2x² + x - 28 = 225
-2x² + x -(28 -225) = 0   {In order to make it true}
-2x² + x +197 = 0           {Now factorise}
X = 10.177 
     or
X = -9.678

Please double check this. 
My first answer was "No real Roots"...But I did it again and got two figures. You'll have to confirm this with a pair. Sorry.