document.write( "Question 983311: find the point(s)P on the xaxis in which the line through g(-4,-3) and P is perpendicular to the line through h(4,9) and P. \n" ); document.write( "
Algebra.Com's Answer #604187 by josgarithmetic(39620)\"\" \"About 
You can put this solution on YOUR website!
(After drawing a graph on a chalkboard and thinking very carefully on this, a solution method began to come to me...)\r
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\n" ); document.write( "\n" ); document.write( "Draw and label a graph of the situation as completely as you can do.
\n" ); document.write( "Show your points G(-4,-3) and H(4,9); and judge what two points (x,y) on the x-axis would form two possible points P(x,y), so that you can draw lines.\r
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\n" ); document.write( "\n" ); document.write( "The four points (two different \"P\"), and G and H will form a trapezoidal figure. Place your two \"P\" points so that PG and PH LOOK AS THOUGH they meet at right angle, or are perpendicular.\r
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\n" ); document.write( "\n" ); document.write( "You will use the slopes of GP and PH.
\n" ); document.write( "Perpendicular lines will have slopes which are negative reciprocals of each other.
\n" ); document.write( "(You really need to know formula for slope of a line for this!)\r
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\n" ); document.write( "\n" ); document.write( "Setup this table.\r
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\n" ); document.write( "\n" ); document.write( "SLOPE________________EXPRESSION
\n" ); document.write( "Line GP______________\"%28y%2B3%29%2F%28x%2B4%29\"
\n" ); document.write( "Line PH______________\"%28y-9%29%2F%28x-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "Again, these slopes must form a product of \"-1\".
\n" ); document.write( "Next setup the equation for this:
\n" ); document.write( "\"highlight_green%28%28%28y%2B3%29%2F%28x%2B4%29%29%28%28y-9%29%2F%28x-4%29%29=-1%29\"\r
\n" ); document.write( "\n" ); document.write( "I here omit a few steps...
\n" ); document.write( "but you should get a step continuing with
\n" ); document.write( "\"y%5E2-6y-27=-x%5E2%2B16\"
\n" ); document.write( "and then continuing,
\n" ); document.write( "\"y%5E2-6y%2Bx%5E2=27%2B16\"
\n" ); document.write( "\"x%5E2%2By%5E2-6y=43\"
\n" ); document.write( "You also MUST know about Completing the Square (maybe, maybe not...)
\n" ); document.write( "\"x%5E2%2By%5E2-6y%2B9=43%2B9\"
\n" ); document.write( "\"highlight_green%28x%5E2%2B%28y-3%29%5E2=52%29\"\r
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\n" ); document.write( "\n" ); document.write( "That looks like it will be complicated to find your point P(x,y); but remember you are looking for possible points ON THE x-AXIS, and therefore \"highlight%28highlight%28y=0%29%29\".\r
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\n" ); document.write( "\n" ); document.write( "NOW, what is x?
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