sides of a box 19 9.1

Question

The sides of the box shown are labeled with the dimensions in feet. What is the value of x if the volume of the box is 405
cubic? feet?

 

Use the formula for? volume, V=LWH, to write an equation describing the given problem. What is the resulting? equation?
 

(x−3)(x−3)(5) = 

 

Answer 1

Assuming your expression represents the products of three dimension,

 

(x - 3)(x - 3)(5) = 405

 

 

Divide both sides of equation by 5 to isolate all x terms.

 

(x - 3)(x - 3) = 81

 

 

(x - 3)² = 81

 

 

Square-root both sides of the equation.

 

x - 3 = ±√81

 

x  = 3 - √81          or              x = 3 + √81

 

 

Accept     x = 3 + √81    as a solution, since dimensions can only be positive.