$-4.5+\left(-5.5\right)+\left(3.1\right)$

$12j+2j-4+3j^2$

$\frac{4t^{2}+3t-1}{t^{3}-t^{2}}$

$25x^6-10x^4+20x^2$

$\left(4x+yz\right)\left(4x-yz\right)$

$\int\left(\frac{2}{19+x}\right)dx$

$\left(\frac{\left(-6^2\right)-\left(-2^2\right)}{\left(-2^2\right)-\left(-6^2\right)}\right)$