Ax+3y=5 fine the missing coefficient (a) and also the completed equation

Find the sum of the measure of the interior angles of a polygon of 9 sides ; of 32 sides

Which system of linear inequalities is graphed? can somebody pleasssse

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