$x\left(28+7x\right)$

$\int\frac{x^2}{\left(x^2+36\right)^{\frac{3}{2}}}dx$

$\left(2.123\right)\cdot\left(-30.6\right)$

$-2x\cdot\left(-5x\right)$

$\left(6d\:\:-\:\:15\:\right)\left(6d+8\right)-\left(12-3\right)^2+5\left(3d-10\right)$

$4\sqrt{3}+8cm$

$3mn+4m+6m-2n+3m$