Translation- moving on the coordinate plane?

What is the slope of a line that is perpendicular to y = 3x + 1

Which best explains why this triangle is or is not a right triangle?

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