Please answer ugrent is worth 30 points

What is the missing reason in step 5? linear pair postulategivendefinition of complementary anglescongruent complements theorem

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

Sammie has 3 times as many goldfish as nora. nora has 4 goldfish. how many goldfish do sammie and nora have in all?