Question

how do u find the x-intercepts of a quadratic function algebraically?

Answer 1

http://www.cs.amherst.edu/~djv/irs.pdf

Answer 2

let y=0

Answer 3

then solve for x

Answer 4

k thanks!

Answer 5

yw

Answer 6

Or for
\[y = ax^{2} + bx + c\]
intercepts will occur at:
\[\frac{-b\pm\sqrt{b^{2}-4ac}}{2a}\]

Answer 7

algebraically? cant be down

Answer 8

there has to be a full moon, dancing, and a sacrificed chicken .... only then will the gods betow upon you the answers to the quadratics

Answer 9

...and maybe even a spellcheck lol

Answer 10

The long way would be:
\[0=ax^{2}+bx+c\]
\[0=4(ax)^{2}+4abx+4ac\]
\[-4ac=4(ax)^{2}+4abx\]
\[b^{2}-4ac=4(ax)^{2}+4abx+b^{2}\]
\[b^{2}-4ac=(2ax+b)^{2}\]
\[\pm\sqrt{b^{2}-4ac}=2ax+b\]
\[-b\pm\sqrt{b^{2}-4ac}=2ax\]
\[\frac{-b\pm\sqrt{b^{2}-4ac}}{2a}=x\]