Please help! I'll mark your answer as brainiest if right <3

Answer:y=9
Step-by-step explanation:
y=mx+9
Swap sides so that all variable terms are on the left hand side.
mx+9=y
Subtract 9 from both sides.
mx=y−9
The equation is in standard form.
xm=y−9
Divide both sides by x.
x
xm
=
x
y−9
Dividing by x undoes the multiplication by x.
m=
x
y−9
Solve for x
{
x=
m
y−9
,
x∈R,
m
=0
y=9 and m=0