# Algebra Question

• Jan 11th 2009, 04:46 PM
MellowCandle
Algebra Question
Hello there,

I found this question online;

http://homepage.ntlworld.com/james.m...amquestion.gif

I don't understand how the person answering has jumped from the equation;

\$\displaystyle kx^2 + 16x + k = 0\$

to;

\$\displaystyle b^2 - 4ac = 0\$

help! (Worried)
• Jan 11th 2009, 04:58 PM
stapel
Quote:

Originally Posted by MellowCandle
I don't understand how the person answering has jumped from the equation;

\$\displaystyle kx^2 + 16x + k = 0\$

to;

\$\displaystyle b^2 - 4ac = 0\$

The Quadratic Formula allows one to solve this sort of equation. The part of the Formula inside the square root is called "the discriminant", and allows you to determine the type of solution.

For a complete explanation, try some of the various lessons available online. Once you are familiar with the discriminant and what information it provides, you will "see" why the solver went straight to the value of "\$\displaystyle b^2 - 4ac\$". :wink:

Have fun! :D