Kim bought a poster that cost 8,95 and some colored pencils. the total cost was 21.35. how much did the colored pencils cost?

Me because some of question i don’t understand

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

Put the equation in slope intercept form by solving for y