Math Help - graph problem..

Stats whether they are parellel perpendicular or neither by working out the gradients....

i) y= -4 x= 2

i have a general idea that the formula y=mx-c is involed, or am i wrong ?Also, how do i solve this question ?

It is involved but you have only one line...

for parallel lines m is the same

for perpendicular lines

so how can i solve it...because thats all its given in the question