document.write( "Question 201101: Find the perfect square trinomial whose first two terms are:
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\n" ); document.write( "\n" ); document.write( "Solve by completing the square.
\n" ); document.write( "t^2 - 3t - 7 = 0\r
\n" ); document.write( "\n" ); document.write( "An object in launched directly upward at 64 feet per second (ft/s) from a platform 80 feet
\n" ); document.write( "high. What will be the object's maximum height? When will it attain this height?\r
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Algebra.Com's Answer #151327 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
1) To find the perfect square trinomial, add the square of half the x-coefficient .
\n" ); document.write( "\"a%5E2-8a%2B%288%2F2%29%5E2\" Simplify.
\n" ); document.write( "\"highlight%28a%5E2-8a%2B16+=+%28a-4%29%5E2%29\"
\n" ); document.write( "2) Solve by completing the square:
\n" ); document.write( "\"t%5E2-3t-7+=+0\" Add 7 to both sides.
\n" ); document.write( "\"t%5E2-3t+=+7\" Now complete the square in t by adding the square of half the t-coefficient to both sides. This is \"%283%2F2%29%5E2+=+9%2F4\".
\n" ); document.write( "\"t%5E2-3t%2B9%2F4+=+7%2B%289%2F4%29\" Factor the left side and simplify the right side.
\n" ); document.write( "\"%28t-%283%2F2%29%29%5E2+=+%2828%2F4%29%2B%289%2F4%29\"
\n" ); document.write( "\"%28t-%283%2F2%29%29%5E2+=+37%2F4\" Take the square root of both sides.
\n" ); document.write( "\"t-%283%2F2%29+=+%28sqrt%2837%29%29%2F2\" or \"t-%283%2F2%29+=+-%28sqrt%2837%29%29%2F2\" Add \"3%2F2\" to both sides of each solution.
\n" ); document.write( "\"highlight_green%28t+=+%283%2Bsqrt%2837%29%29%2F2%29\" or \"highlight_green%28t+=+%283-sqrt%2837%29%29%2F2%29\"
\n" ); document.write( "3) Use the formula for the height of an object propelled upward with an initial velocity of \"v%5B0%5D\" ft/sec from an initial height of \"h%5B0%5D\" feet. \"G+=+32+ft%2F%28sec%29%5E2\":
\n" ); document.write( "\"h%28t%29+=+-%281%2F2%29Gt%5E2%2Bv%5B0%5Dt%2Bh%5B0%5D\" Substitute \"v%5B0%5D+=+64\" and \"h%5B0%5D+=+80\"
\n" ); document.write( "\"highlight%28h%28t%29+=+-16t%5E2%2B64t%2B80%29\" First find the time t at which the object reaches its maximum height. Remember that this equation, when graphed, will show a parabola that opens downward so that the vertex of the graph will be the maximum point of the curve or the time of maximum height, t.
\n" ); document.write( "The vertex of this parabola is given by \"t+=+-b%2F2a\" where a = -16 and b = 64, so...
\n" ); document.write( "\"t+=+-%2864%29%2F2%28-16%29\"
\n" ); document.write( "\"t+=+64%2F32\"
\n" ); document.write( "\"highlight%28t+=2%29\"seconds.
\n" ); document.write( "The object will attain its maximum height in 2 seconds. To find the maximum height of the object, subtitute t = 2 into the beginning equation \"highlight%28h%28t%29%29\"and solve for h.
\n" ); document.write( "\"h%282%29+=+-16%282%29%5E2%2B64%282%29%2B80\"
\n" ); document.write( "\"h%282%29+=+-64%2B128%2B80\"
\n" ); document.write( "\"highlight%28h%282%29+=+144%29\"feet is the maximum height attained by the object..
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