Put the equations in slope-intercept form and identify the equations as parallel orperpendicular lines.
Slope-intercept form for 
3
x
+
y
=
7
 : 
Slope-intercept form for 
3
y
=
-
x
-
3
 : 
Are the lines parallel or perpendicular? 
a. 
y
=
3
x
+
7
b. 
y
=
1
3
x
+
1
c. 
y
=
-
1
3
x
-
1
d. 
y
=
-
7
x
+
3
e. Perpendicular 
f. Parallel​