$169-196z^4$

$-2y-y$

$5sen\left(x\right)+cos^2\left(x\right)+2sen^2\left(x\right)=4$

$\frac{64x^3y}{2^3xy}$

$32x^2=17-18x$

$\cos\left(y\right)\frac{dx}{dy}=x\sin\left(y\right)+\tan\left(y\right)$

$306=\left(9-2x\right)\left(30-2x\right)+2\left(30-2x\right)\left(x\right)+2\left(9-2x\right)\left(x\right)$