$99\:-\:\left(-68\right)$

$\left(x+y+32\right)^2$

$23^2$

$w^2+20w+36$

$\frac{1}{\sin\:\left(\theta\:\right)}\sin\:\left(\theta\:\right)=1$

$\lim_{x\to\frac{\pi}{2}}\left(\frac{cos\left(x+\pi\right)}{sin\:\left(x+\frac{\pi}{2}\right)}\right)$

$\left(x-y+3z\right)+\left(5x-7y+8z\right)+\left(\left(-6x-9y+5z\right)\right)$