document.write( "Question 480989: graph using the slope intercept
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Algebra.Com's Answer #329497 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
a) y=3x+1
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document.write( "I'll do the second one first, since it requires more work,\r\n" );
document.write( "then I'll do the first one:\r\n" );
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document.write( "Solve it for y:\r\n" );
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document.write( "3x - 4y = 12\r\n" );
document.write( "    -4y = -3x + 12\r\n" );
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document.write( "Divide through by 4\r\n" );
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document.write( "    \"%28-4%29%2F%28-4%29\"y = \"%28-3%29%2F%28-4%29\"x + \"12%2F%28-4%29\"\r\n" );
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document.write( "          y = \"3%2F4\"x - 3\r\n" );
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document.write( "compare that to \r\n" );
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document.write( "          y = mx + b\r\n" );
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document.write( "the slope m is \"3%2F4\" and the y-intercept is (0,b) or (0,-3)\r\n" );
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document.write( "We begin at the y-intercept (0,-3):\r\n" );
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document.write( "         \r\n" );
document.write( "We take the numerator of the slope which is 3, and since the\r\n" );
document.write( "slope is positive we draw a line from the y-intercept UPWARD\r\n" );
document.write( "3 units, like the green arrow below. [If the slope had been\r\n" );
document.write( "negative, which it wasn't, we would have draw the arrow downward]\r\n" );
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document.write( "Now we take the denominator of the slope which is 4, and draw a \r\n" );
document.write( "another line from that green arrow head to the RIGHT 4 units, as \r\n" );
document.write( "shown below. [Even if the slope had been negative, we still would have \r\n" );
document.write( "drawn the arrow to the RIGHT the number of units indicated by the\r\n" );
document.write( "denominator of the slope.]\r\n" );
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document.write( "Now get a ruler or straight edge and draw a straight line\r\n" );
document.write( "through the y-intercept (0,-3) and through the second arrow head:\r\n" );
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document.write( "-----------------------------\r\n" );
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document.write( "Now I'll do the first one:\r\n" );
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document.write( "          y = 3x + 1\r\n" );
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document.write( "It is already solved for y and is in slope-y-intercept form,\r\n" );
document.write( "so we don't have to do that like we did in the other one:\r\n" );
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document.write( "compare that to \r\n" );
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document.write( "          y = mx + b\r\n" );
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document.write( "the slope m is 3 and the y-intercept is (0,b) or (0,1)\r\n" );
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document.write( "As before we begin at the y-intercept (0,1):\r\n" );
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document.write( "        \r\n" );
document.write( "Now the slope 3 in this one doesn't have a visible denominator,\r\n" );
document.write( "so we write it as \"3%2F1\" so it will have both a numerator and\r\n" );
document.write( "a denominator:  \r\n" );
document.write( "\r\n" );
document.write( "We take the numerator of the slope which is 3, and since the\r\n" );
document.write( "slope is positive we draw a line from the y-intercept UPWARD\r\n" );
document.write( "3 units, like the green arrow below. [If the slope had been\r\n" );
document.write( "negative, which it wasn't, we would have draw the arrow downward]\r\n" );
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document.write( "Now we take the denominator of the slope which is 1, and draw a \r\n" );
document.write( "another line from that green arrow head to the RIGHT 1 unit, as \r\n" );
document.write( "shown below. [Even if the slope had been negative, we still would have \r\n" );
document.write( "drawn the arrow to the RIGHT the number of units indicated by the\r\n" );
document.write( "denominator of the slope.]\r\n" );
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document.write( "Now get a ruler or straight edge and draw a straight line\r\n" );
document.write( "through the y-intercept (0,1) and through the second arrow head:\r\n" );
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document.write( "Edwin
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