Let $x$ be a real number,

Factor the following expressions:

$J=x^2+6x+9$

$=.$

$=$

$K=5x^2-2\sqrt[\phantom{2}]{5}x+1$

$=$

$=$

$L=7x^2-1$

$=.$

$=$

On pose $M=\frac{289{10}^{-6}7}{2^3{10}^{-2}{5}^3}$

a$)$ Show that $M=202310-7$

$M=$