Try this: $x^2 = 2x + 5$. Try something more compliated:
$$\displaystyle\int_{-\infty}^{\infty}dx\ e^{-x^2} = \sqrt{\pi}\ \ \ \ \ (1)$$
$$ \delta^L = \nabla_{a}C\odot\sigma'(z^l)\ \ \ \ \ (2)$$
Looks good! How about:
$$i\hbar\dfrac{\partial}{\partial t}|\psi\rangle = \hat{H}|\psi\rangle\ \ \ \ \ (3)$$