Expand the following and simplify the answer as far as possible.
$2x(3+x)-3(x-2)$

Expand the following and simplify the answer as far as possible.

$3(x-5)-(3+x)$

Expand the following and simplify the answer as far as possible.

$2x(3x+1)-2(3-2x)$

Solve the following equation: 

$4x+3=31$

Solve the following equation:

$8x+42=2$

Solve the following equation:

$6x-1=53$

Solve the following equation:

$7x-4=-66$

Solve the following equation:

$9y+7=52$

Solve the following equation:

$11n-19=102$