Step-by-step explanation:
Linear function:
[tex]y=mx+b\\Ax+By=C\\Ax+By+C=0[/tex]
[tex]y=x\qquad\bold{YES}\\\\y=7\qquad\bold{YES}\\\\2y=x^2\qquad\bold{NO}\ \boxed{x^2}\\\\y=4x^2+3x\qquad\bold{NO}\ \boxed{x^2}\\\\3x+4y=12\qquad\bold{YES}\\\\2x^2+6y=12\qquad\bold{NO}\ \boxed{x^2}[/tex]
