How many solutions does the system have?
5y = 15x -- 40
y =3x-- 8

I  dont  know much about vertexes but i know to solve this function you need to use foil method and then corresponmd the vertex with the actual coordinates, hope i !

1. use commutative property to reorder the terms.2x+81=0.2. move the constant to right side by adding its opposite on both sides. 2x+81-81=0-81.2x=(-81).3. divide the equation on both sides.2x ÷ 2 = 81 ÷ 2.x = -81/2. your answer is -81/2. if you need to simplify it into a decimal, it’s -40.5.