SOLUTION: An open rectangular tank has a square base of side x and height u. The surface area of the tank is Sm^2 and its volume is Vm^3. Show that S = 4V/x + x^2.

Algebra ->  Surface-area -> SOLUTION: An open rectangular tank has a square base of side x and height u. The surface area of the tank is Sm^2 and its volume is Vm^3. Show that S = 4V/x + x^2.      Log On


   



Question 1031479: An open rectangular tank has a square base of side x and height u. The surface area of the tank is Sm^2 and its volume is Vm^3. Show that S = 4V/x + x^2.
Found 2 solutions by Boreal, josgarithmetic:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Draw this.
The surface area is x^2 (the base) plus 4xh (the sides)
The volume is x^2*h
solve for h=v/x^2
substitute back into S=x^2+4xh
S=x^2+4*x*v/x^2
S=4v/x + x^2

Answer by josgarithmetic(39621) About Me  (Show Source):
You can put this solution on YOUR website!
V=ux%2Ax
V=ux%5E2
V%2Fx%5E2=u
u=V%2Fx%5E2


S=ux%2Bux%2Bux%2Bux%2Bx%5E2
S=4ux%2Bx%5E2
Substitute for u.
S=4%28V%2Fx%5E2%29x%2Bx%5E2
S=4%28Vx%2Fx%5E2%29%2Bx%5E2
S=4V%2Fx%2Bx%5E2