3x - 4y = 28
-4y = -3x + 28
y = (-3/-4)x + (28/-4)
y = 3/4x - 7........slope is 3/4....y int is (0,-7)
4x + 10y = 20
10y = -4x + 20
y = (-4/10)x + (20/10)
y = - 2/5x + 2.....slope is -2/5.....y int is (0,2)
so ur 2 equations in slope intercept form are :
y = 3/4x - 7 and y = -2/5x + 2
These equations will have one solution, (180/23, -26/23)...they are neither parallel or perpendicular.