Question

Determine whether the graphs of y=-7x-4 and -y=7x+4 are parallel, perpendicular, coincident or none of these

Answer 1

we are given

$y=-7x-4$

$-y=7x+4$

we can multiply -1 on both sides of second equation

$-1*-y=-1(7x+4)$

$y=-7x-4$

we can see that

both equations becomes same

so, they are coincident............Answer

Answer 2

The graphs of y=-7x-4 and -y=7x+4 are coincident.