The base of solid is given by 9x² +4y = 36 on the xy-plane. The cross section is a square that is perpendicular to x-axis. Find the volume by stacking cross section area along x-axis.

A gift box is made in the shape of a triangular prism. The triangular end is an equilateral triangle with length x cm and the length of the box is The volume of the box is 300 cm³. r cmX Кx ст у ст х ст (a) Find an expression for y in terms of x. (b) Show that the total surface area A cm?, of the box, is given by 1200v3, v3x? 2 A = (c) Find the value of x that gives the minimum total surface area. Justify your answer.