<PRE><B>Question 927568</B>
Height (h)= 18 in
30 inch screen means its diagonal length is 30 inches
so diagonal  = 30 inches
wide is unknown
as per pythagorean theorem
 {{{ diagonal^2 =height^2+wide^2}}}
{{{ 30^2= 18^2+wide^2}}}
  {{{ 900=324 +wide^2}}}
   move 324 to the left
 
  {{{900-324 = wide^2}}}
 {{{ 576 =wide^2}}}
  apply square root on both sides
 {{{ sqrt(576) =sqrt(wide^2)}}}
       24 = wide
    Result : wide  =24 inches

 
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