Posted by Bonnie on Wednesday, July 8, 2009 at 3:18pm.
Use the quadratic formula to find the exact solutions of the equation. Show work. Simplify the final results as much as possible.
4x^2 – 16x + 25 = 0.

Algebra  Marth, Wednesday, July 8, 2009 at 3:25pm
The exact question was asked by Pamela yesterday. I have copied down my solution. For more information, view the entire thread.
(a) The equation is in the form ax^2 + bx + c
Use those values for b^2  4ac.
(16)^2  4*4*25
= 256  400
= 144
The determinant is negative, so there will be two imaginary solutions.
(b) The quadratic equation is x = (b +/ sqrt(determinant))/(2a)
Using the values of a, b, and c from the equation, we get
x = (16 +/ sqrt(144))/(2*4)
x = (16 +/ 12i)/8
x = 2 +/ 3i/2