What is 7 times 7 + 7 ?

What does x = in this equation x+3+2x=x+5

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

Factor k2 - 17k + 16. a.(k - 2)(k - 8) b.(k - 1)(k + 16) c.(k - 1)(k - 16)