Please help me please im so confused

3. solve by graphing: y = 2x + 6 x + y = -3

Two lines parallel to a third line are parallel to each other. always sometimes or never

Find the volume of the described solid. the solid lies between planes perpendicular to the x-axis at x = 0 and x=7. the cross sectionsperpendicular to the x-axis between these planes are squares whose bases run from the parabolay=-31x to the parabola y = 30/x. a) 441b) 147c) 864d) 882