Question

solve the system x=3y+9 and 9-x=-3y

Answer 1

hi welcome to openstudy!!

do you know how to apply substitution method?

Answer 2

since equation is already arranged in terms of x,, substitute this equation into the second equation. it will look like this:
x=3y+9 ->eqn 1
9-x=-3y ->eqn 2

sub eqn 1 to eqn 2:
9- (3y+9)=-3y

now can you simplify this new equation and solve for y?

Answer 3

@Annie17 still there?

Answer 4

Yes I am. And I can simplify it now. Thank you. :)