Answer:
Since parallel lines have an equal gradient,
• lines y=3x+4 and y=3x are parallel to each other (they have an equal gradient of y=3x)
Hi, there.
_______
If lines are parallel, their slopes are equal.
Here only
[tex]\leadsto\boldsymbol{y=3x+4\ \& \ y=3x}[/tex]
have equal slopes.
Only these two lines are parallel.
Thus,
[tex]\leadsto\begin{cases}\boldsymbol{y=3x+4}\\\boldsymbol{y=3x} \end{cases}[/tex]
Hope the answer - and explanation - made sense,
happy studying.
