Ineed and i need more practice one this

To solve the system of equations below, grace isolated the variable y in the first equation and then substituted into the second equation. what was the resulting equation? 3y=12x x^2/4+y^2/9=1

3x = 729 solve for x plz . it's urgent. will mark

Select the correct answer from each drop-down menu the equation of a line is 3/5*+1/3y=1/15