What is t equal to in the equation 6t-1/6=9

What is the solution to the system of the equations? x = y - 3 x + 3y = 13

With number 11 ( show how you got the answer)

5. which description does not guarantee that a quadrilateral is a squar ajo is a parallelogram with perpendicular diagonals 0% has all sides congruent and all angles congruent o has all right angles and has all sides congruent 10% is both a rectangle and a rhombus 30%