Question 805405
Neither.
If two lines are parallel, they have the same slope.
If two lines are perpendicular, the product of their slopes is {{{-1}}}.
 
To find the slope we could solve for y to get the slope intercept form of the equation.
We do not really need the intercept. We only need the slope, but it's not hard.
{{{3x+4y=12}}}-->{{{4y=-3x+12}}}-->{{{y=(-3/4)x+12/4}}}-->{{{y=(-3/4)x+3}}}
{{{6x+2y=7}}}-->{{{2y=-6x+7}}}-->{{{y=(-6/2)x+7/2}}}-->{{{y=-3x+7/2}}}
The slopes are {{{-3/4}}} and {{{-3}}}.
They are not the same number, so the lines are not parallel.
When you multiply them,
{{{(-3/4)(-3)=9/4}}},
you do not get {{{-1}}}, so the lines are not perpendicular either.
 
Maybe, to find slopes, you've been told that for a linear equation in the form {{{Ax+By=C}}}
(like {{{3x+4y=12}}} and {{{6x+2y=7}}}),
the slope is {{{-A/B}}},
which means take the coefficient of the x, change its sign, and divide it by the coefficient of the y.
Maybe you are expected memorize formulas and do that.
With{{{3x+4y=12}}}, you take the {{{A=3}}}, change it into {{{-A=-3}}}, and divide by {{{B=4}}} to get {{{-3/4}}} 
With {{{6x+2y=7}}}), you take the 6, change it to -6, and divide by 2 to get {{{-3}}}