-7/2(2x+6/7)-3

(-7/2)(2x+6/7)-3      distribute the -7/2 over the terms in the parentheses

(-14/2)x - 42/14 - 3  =

-7x - 3 - 3 =

-7x - 6

I don't think this is even possible because there is no equal sign

$${\mathtt{\,-\,}}{\frac{{\mathtt{7}}}{{\mathtt{2}}}}{\mathtt{\,\times\,}}\left({\mathtt{2}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{6}}}{{\mathtt{7}}}}\right){\mathtt{\,-\,}}{\mathtt{3}}$$

First you distribute the -7/2.

$${\mathtt{\,-\,}}\left({\frac{{\mathtt{7}}}{{\mathtt{2}}}}{\mathtt{\,\times\,}}\left({\mathtt{2}}\right)\right) = -{\mathtt{7}}$$

$${\mathtt{\,-\,}}\left({\frac{{\mathtt{7}}}{{\mathtt{2}}}}{\mathtt{\,\times\,}}\left({\frac{{\mathtt{6}}}{{\mathtt{7}}}}\right)\right) = -{\mathtt{3}}$$

This makes the equation into something a bit more legible.

$$\left({\mathtt{\,-\,}}{\mathtt{7}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{3}}\right){\mathtt{\,-\,}}{\mathtt{3}}$$

Then you just subtract 3.

$$\left({\mathtt{\,-\,}}{\mathtt{7}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{3}}{\mathtt{\,-\,}}{\mathtt{3}}\right)$$

$$\left({\mathtt{\,-\,}}{\mathtt{7}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{6}}\right)$$

At this point you can drop the parentheses and you have your most simplified answer: -7x - 6