What are the solutions of the system 7x + 3y = -3 and y = -2x? (-1, 0) and (0, -1) (-8, 3) and (3, -8) (-1, 0) and (-8, 3) (0, -1) and (3, -8)

Answer question above and explain each step : )

The border line of the linear inequality 4x + 7y < 5 is dotted true or false?

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)