I really need help on quiz.

To solve the system of equations below, pedro isolated the variable y in the first equation and then substituted it into the second equation. what was the resulting equation? { 5y=10x {x^2+y^2=36

Table which ratio is equivalent to 3: 7? 6: 7 3: 21 24: 56 15: 30

What is the distance from zero if a quadratic function has a line of symmetry at x=-3 and a zero at 4