Answer
a. $6$
b. $6$ is not a solution of the equation
Work Step by Step
$a.$
Replace x with 3 and y with 6:
$6x-2y=$
$=6(3)-2(6)$
$=18-12$
$=6$
b.
If the number $6$ is the solution to the equation, then replacing $w$ with $6$ should result in a valid equation (the left side should be equal to the right side of the equality sign)
$7w=45-2w\quad?$
$7(6)=45-2(6)\quad?$
$42=45-12\quad?$
No, the equation is not valid, $6$ is not a solution of the equation.
