Thread: Quadratic

Perform the quadratic equation on the following:

9x² + 25 = 0

Originally Posted by Trentt

Perform the quadratic equation on the following:

9x² + 25 = 0

i think you mean solve the quadratic equation, you cant "perform" an equation. first just to clarify, are you sure it wasn't 9x^2 - 25 = 0?

if not, the equation has no real solutions, the solutions will be complex numbers. so here goes.

9x^2 + 25 = 0
=> 9x^2 = -25
=> x^2 = -25/9
=> x = +/- sqrt(-25/9)
=> x = +/- sqrt(25/9)i
=> x = +/- 5/3 i

yeah, it wanted complex numbers, ty

Originally Posted by Trentt

Perform the quadratic equation on the following:

9x² + 25 = 0

o i get what you mean now, you mean use the quadratic formula to solve it.
ok, here goes:

9x^2 + 25 = 0

=> x = [0 +/- sqrt(0 - 4(9)(25)]/2(9)
=> x = +/- sqrt(-900)/18
=> x = +/- sqrt(900)i/18
=> x = +/- 30/18 i
=> x = +/- 5/3i