Question 934190

if you cut away the {{{5}}} inches on each corner, the new dimensions are {{{(2x-10)}}} and {{{(x-10)}}}. 
If you were to fold the corners up, the height is {{{5}}}.
The equation for the volume is:

{{{ 5(2x-10)(x-10) =1760}}}
{{{ (2x-10)(x-10) =1760/5}}}
{{{ 2x^2-20x-10x+100 =352}}}...all terms divide by {{{2}}}

{{{ x^2-10x-5x+50 =176}}}

{{{ x^2-15x-126=0}}}...factor 

{{{ x^2-21x+6x-126=0}}}

{{{ x(x-21)+6(x-21)=0}}}

{{{ (x-21)(x+6) = 0}}}

solutions:

if {{{ (x-21) = 0}}}=> {{{x=21}}}

if {{{ (x+6) = 0}}}=> {{{x=-6}}}...we don't need negative solution

so, {{{x= 21}}}

the dimensions of the metal are {{{21in}}} by {{{42in}}}