document.write( "Question 145017: Problem: The mainsail on a sailboat is a right triangle in which the hypotenuse is called the leech. A 12-foot tall mainsail has a leech of 13 feet. If sailcloth costs $10.00 per square foot, what is the cost of a new mainsail?
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Algebra.Com's Answer #105762 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
To answer this question, you need to know the \"area\" of the sail. The area of any triangle is 1/2(base)(height).\r
\n" ); document.write( "\n" ); document.write( "The key is that they told you that it is a \"right-triangle\". Knowing that, you can apply Pythagorean's theorem to find the length of the base of the sail.\r
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\n" ); document.write( "\n" ); document.write( "Let x = length of the base of the sail
\n" ); document.write( "then
\n" ); document.write( "x^2 + 12^2 = 13^2
\n" ); document.write( "x^2 + 144 = 169
\n" ); document.write( "x^2 = 25
\n" ); document.write( "x = 5 feet\r
\n" ); document.write( "\n" ); document.write( "Area of sail:
\n" ); document.write( "1/2(base)(height)
\n" ); document.write( "= 1/2(5)(12)
\n" ); document.write( "= 5(6)
\n" ); document.write( "= 30 sq ft\r
\n" ); document.write( "\n" ); document.write( "At $10 per sq ft then the total cost is:
\n" ); document.write( "10 * 30 = $300\r
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