$4y^2-56y+196$

$16x^2y^2-36x^2$

$12x^3-36x^2-48x=0$

$\left(2-2\sin\left(x\right)\right)\left(1+\sin\left(x\right)\right)$

$\lim_{x\to6}\left(\frac{x^3-5t+100}{x^2-t-30}\right)$

$\left(-5+3\right)\left(4\right)\left(-5\right)$

$-4\left(x+9\right)+3\left(x-y\right)+5y$