What number can be written as 40 plus 5

Which triangles area would be calculated using the trigonometric area formula

Two parallel lines are crossed by a transversal.what is value of x

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