Question

I need help with some of the questions on my study guide for my test!! please and thank you!!

Determine whether the equations represents direct variation if it does give the constant of variation
1.) 2y=5x+1
2.)-12x=6y
3.)0.7x-1.4 y=0
Suppose y varies directly with x write a direct variation equation that relates x and y
4. y=-10 when x=2
5.y=7 1/2 when x=3
6.y=10.4 when x=4