Someone can u please help me, ill give u 25 points, :D

If 20% of a number is 35, what is 50% of that number?

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

Ill mark the brainliest if you me with the these three questions 7,8,9