A rectangular LCD has an area of 480 cm2 and a perimeter of 92 cm. If the size of the LCD is defined in term of length of the diagonal, then what is the size of the LCD?
Answer & explanation
Correct answer: option 1
We have,
The perimeter of a rectangular LCD = 92m.
Area = 480m2
Then 2(l + b) = 92
L+ b = 46 … (A)
And lb = 480 ….(B)
Now, we know that,
(l - b)2 = (l + b)2 - 4lb
= (l –b)2 = 2116 - 4 × 480
= (l –b)2 = 2116 - 1920 = 196
(l - b) = 14 ….(C)
From, equation (A) and (C)
B = 16, and l = 30
Then (Diagonal)2 = 302 + 162
(Diagonal)2 = 1156
Diagonal = 34.