Determine whether equation is parallel or perpendicular or neither 9x+3y =12 and 12x +4y =7

The standard linear equation is y=mx+b
To be perpendicular the slope (m) has to be a negative.
reciprocal (2 and -1/2)
To be parallel the slope (m) has to be equal.
So put the equations in standard for
First you get:
3y=-9x+12 and
4y=-12x+7
You then have to divide the terms in front of the y's. You have to divide.
You get:
y=-3x+4 and
y=-3x+7/4
The -3's are the slopes (m)
-3=-3 so:
The lines are parallel