$\frac{1000x^3-8y}{6x-8y^3}$

$65\:-\:\left(-30\right)\:+\:\left(-45\right)\:-\:\left(-5\right)\:+\:40\:-\:10$

$\frac{x-2}{x+3}=2$

$\left(-3x^7-x^5-1\right)-\left(x^5-1\right)$

$x^2+10\cdot x+25\cdot x^2+10\cdot x+25$

$\left(5^2\right)\left(6^2\right)\left(5^3\right)\left(6\right)$

$x^2+14x+40=0$