315 divide by 9= 36
2*36=72
7*36= 252
72:252
D.
Because 4 divided by 2 is 2
It is true because if a is perpendicular to b and b is perpendicular to c therefore a has to be perpendicular to c also they said that all three lines are coplanar therefore the statement must be true
I hope this helped you out :)
It's hard to help if you can't provide everything with the question