1

$\begin{array}{cc}2y& =4x+3\\ 8y& =16x-3\end{array}$

parallel

skew

perpendicular

✗✓

2

$\begin{array}{cc}7y-x& =8\\ 7x-y& =8\end{array}$

parallel

skew

perpendicular

✗✓

3

$\begin{array}{cc}3y& =2-x\\ 2x& =-6y+7\end{array}$

parallel

skew

perpendicular

✗✓

4

$\begin{array}{cc}2+4x& =3y\\ 3y+4x& =2\end{array}$

parallel

skew

perpendicular

✗✓

5

$\begin{array}{cc}3y& =2x+2\\ 2y& =3x+2\end{array}$

parallel

skew

perpendicular

✗✓

6

$\begin{array}{cc}y& =5x-2\\ 5y& =-x+6\end{array}$

parallel

skew

perpendicular

✗✓