4x2 – 2x – 5 = 0
Now instinct would tell you oh plug it all in but no. Instead you add 5 to the other side of the equation. I know this is completely different then what you're used to, but trust me on this. After adding five you're left with
4x2 – 2x = 5
Now there are a few steps you have to do now. First you have to get rid of the four so that there is no coefficient in front of the squared term. Now after that you divide the second term by 2 and then square it. Whatever you get you add it to both sides.That was a lot of information, but this is how you do it.
See not that hard? Now you have completed the square but your answer isn't finished. Now you take the square root of both sides of the equation.

You're almost done now! All that;s left is solving for X. The change to the plus or minus symbol signifies that you will have two answers. Remember quadratics are square because you have two answers.
You're final answer looks something like:
See not so bad huh? It takes some getting used to but once you master these steps you'll be solving quadratics by completing the square all the time. Unless of course you love that quadratic formula.



No comments:
Post a Comment