document.write( "Question 1042983: Find the straight lines which have slope -1 and form a triangle of area 8 square units with coordinate axes.\r
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Algebra.Com's Answer #658054 by Edwin McCravy(20055) $\"\"$ $\"About$

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Since the slope is -1, we substitute -1 in the\r\n" );
document.write( "slope intercept form\r\n" );
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document.write( "y = mx + b \r\n" );
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document.write( "and get\r\n" );
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document.write( "y = -1x + b\r\n" );
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document.write( "or\r\n" );
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document.write( "y = -x + b\r\n" );
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document.write( "The y coordinate is (0,b).\r\n" );
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document.write( "We find the x-intercept by substituting y=0 and solving\r\n" );
document.write( "for x:\r\n" );
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document.write( "0 = -x + b\r\n" );
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document.write( "x = b\r\n" );
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document.write( "So the x-intercept is (b,0)\r\n" );
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document.write( "We graph a typical such line:\r\n" );
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document.write( "We want the area of the green triangle:\r\n" );
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document.write( "The area of a triangle is given by the formula:\r\n" );
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document.write( "The base is b and the height is also b\r\n" );
document.write( "We are give that the area = 8, substituting:\r\n" );
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document.write( "Multiply through by 2\r\n" );
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document.write( "Take square roots of both sides, remembering ą\r\n" );
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document.write( "So there are two triangles. One for b=4 and one \r\n" );
document.write( "for b=-4, the two green triangles below:\r\n" );
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document.write( "Edwin

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