$5x^2\:-\:4xy\:+7y^2\:-\:\left(-6x^2\:+\:3xy\:-\:2y^2\right)\:$

$2x^2+y^2=8$

$17-21.9$

$2\left(0.1\right)^2-3\left(0.1\right)$

$5+\left[2-\left(4+5-3\right)+6\right]-1-\left(3+5\right)$

$\frac{4^{0}\cdot5^{3}\cdot8^{10}}{2^{2}\cdot4^{2}\cdot5^{3}}$

$5\left(x+2\right)^3-3\left(x+2\right)^2\left(x-2\right)$