Question 782142
width = x
length = x+10 in

2 inch is cut from both ends
so width = x-2
and 
length = x+10-2=x+8

The dimensions of the box 

x-2-----width
x+8  length
2inch = height


Volume = L * W *h

(x-2)(x+8)*2=832

x^2+6x-16=832/2

x^2+6x-16=416

x^2+6x-432=0

Find the roots of the equation by quadratic formula							
							
a=	1    	b=	6	c=	-432		2916
							
b^2-4ac=	36	-	-1728				
b^2-4ac=	1764		{{{sqrt(	1764	)}}}=	42	
{{{x=(-b+-sqrt(b^2-4ac))/(2a)}}}							
{{{x1=(-b+sqrt(b^2-4ac))/(2a)}}}				)/			
x1=(	-6	+	42	)/	2		
x1=	18						
x2=(	-6	-	42	)/	2		
x2=	-24						
Ignore negative value							
x	=	18	

width = 18 inch

length = 10+8 =18 inc