Answer:
C=30
Step-by-step explanation:
Supposing that we have the lines
x+2=10y
and
3x+6=Yc.
Note that dividing by 3 the second line can be rewritten as
x + 2= Y c/3.
Remember that a line is written as [tex]ax+b=dY[/tex], in our case, both lines have [tex]a=1[/tex] and [tex]b=2[/tex]. Therefore, in orther that the two lines are equal, we need that [tex]10=c/3[/tex], hence [tex]c=30.[/tex]