Question

How do you find the roots, real and imaginary, of `y=10x^2 + 9x-1` using the quadratic formula?

Answer 1

`x_(1,2)=(-B+-sqrt(B^2-4AC))/(2A)`

Explanation:

`x_(1,2)=(-9+-sqrt((-9)^2-4*10*(-1)))/(2*10)`

`x_(1,2)=(-9+-sqrt(81+40))/(20)`

`x_(1,2)=-9/20+-1/20sqrt121=-9/20+-11/20`

`->x_1=-9/20+11/20=2/20=1/10`

`->x_2=-9/20-11/20=-20/20=-1`