# Math Help - easy and quick one

1. ## easy and quick one

Erasing x^2 in a cubic equation.

2. Try to find $a$ such that, if you replace $x$ by $y-a$ and expand, the coefficient in front of $y^2$ is zero.

3. Originally Posted by ardam
Erasing x^2 in a cubic equation.
If you have $x^3 + ax^2+bx+c = 0$ let $y = x + \frac{a}{3}$.
That should remove the $x^2$ term.

4. cheers for the help