document.write( "Question 249403: The diagonal of a television set is 52 inches long. Its length is 28 inches more than its height. Find the dimensions of the television set. \n" ); document.write( "
Algebra.Com's Answer #181666 by oberobic(2304)\"\" \"About 
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The diagonal of the TV can be considered the hypotenuse of a right triangle. It can be solved using the Pythagorean formula:
\n" ); document.write( "\"C%5E2+=+A%5E2+%2B+B%5E2\"
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\n" ); document.write( "Assuming L is the width of the TV set, which the problem calls \"length\", and H is the height of the screen.
\n" ); document.write( "\"L+=+H+%2B+28\"
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\n" ); document.write( "Returning to the Pythagorean formula...
\n" ); document.write( "\"D+=+diagonal+=+52\"
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\n" ); document.write( "\"D%5E2+=+L%5E2+%2B+H%5E2\"
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\n" ); document.write( "Substituting L = H+28
\n" ); document.write( "\"D%5E2+=+%28H%2B28%29%5E2+%2B+H%5E2\"
\n" ); document.write( "\"52%5E2+=+%28H%2B28%29%28H%2B28%29+%2B+H%5E2\"
\n" ); document.write( "\"52%5E2+=+H%5E2+%2B+28H+%2B+28H+%2B+784+%2B+H%5E2\"
\n" ); document.write( "\"52%5E2+=+2H%5E2+%2B+56H+%2B+784\"
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\n" ); document.write( "Squaring 52
\n" ); document.write( "\"2704+=+2H%5E2+%2B+56H+%2B+784\"
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\n" ); document.write( "Dividing both sides by 2
\n" ); document.write( "\"1352+=+H%5E2+%2B+28H+%2B+392\"
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\n" ); document.write( "Subtracting 1352 from both sides
\n" ); document.write( "\"0+=+H%5E2+%2B+28H+%2B+392+-+1352\"
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\n" ); document.write( "Simplifying
\n" ); document.write( "\"0+=+H%5E2+%2B+28H+-960\"
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\n" ); document.write( "Can 960 be factored such that the two terms are 28 apart?
\n" ); document.write( "Yes. 48*20 = 960 and 48-20=28
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\n" ); document.write( "\"%28H%2B48%29%28H-20%29+=+0\"
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\n" ); document.write( "So we have two candidate solutions: H= -48 and H = 20. Since a negative height is nonsense, then our suggested answer is:
\n" ); document.write( "\"H+=+20\"
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\n" ); document.write( "Looking back to our defined equations,
\n" ); document.write( "\"L+=+H+%2B+28+=+20+%2B+28+=+48\"
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\n" ); document.write( "Checking by using the Pythagorean formula:
\n" ); document.write( "\"D+=+52\"
\n" ); document.write( "\"L%5E2+=+48%5E2+=+2304\"
\n" ); document.write( "\"H%5E2+=+20%5E2+=+400\"
\n" ); document.write( "\"L%5E2+%2B+H%5E2+=+2704\"
\n" ); document.write( "\"sqrt%282704%29+=+52\"
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\n" ); document.write( "So that checks just fine.
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\n" ); document.write( "But is it an analog TV or an HDTV?
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\n" ); document.write( "Analog TV has a ratio of width to height of 4:3. The picture is 4 units wide by 3 units high.
\n" ); document.write( "HDTV has a ration of 16:9. The picture is 16 units wide by 9 units high.
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\n" ); document.write( "Our proposed TV set has a picture that is 48 wide by 20 high. That is a ratio of 48:20, or 24:10, or 12:5. This does not correspond to any real TV set. So perhaps a negative height would work when solving an \"imaginary\" TV problem. Hmmm...
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