document.write( "Question 513312: what is the slope and y-intercept of 4x+3y=12 \n" ); document.write( "
Algebra.Com's Answer #342953 by Edwin McCravy(20056)\"\" \"About 
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document.write( "4x + 3y = 12   \r\n" );
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document.write( "We must get it in the slope-y-intercept form: y = mx + b.\r\n" );
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document.write( "We subtract 4x from both side:\r\n" );
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document.write( " 4x + 3y = 12\r\n" );
document.write( "-4x            -4x\r\n" );
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document.write( "      3y = 12 - 4x\r\n" );
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document.write( "We swap the terms on the right because the form y = mx + b has the x term first\r\n" );
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document.write( "      3y = -4x + 12\r\n" );
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document.write( "We divide all three numbers by 3\r\n" );
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document.write( "      \"3%2F3\"y = \"%28-4%29%2F3\"x + \"12%2F3\"\r\n" );
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document.write( "Simplify\r\n" );
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document.write( "       y = \"-4%2F3\"x + 4   \r\n" );
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document.write( "Next we compare that to\r\n" );
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document.write( "       y = mx + b   which has slope m and y-intercept (0,b)\r\n" );
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document.write( "We can see that m = \"-4%2F3\" and that b = 4 so the y-intercept\r\n" );
document.write( "is the point (0,4)\r\n" );
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document.write( "The graph is below.  Notice that the y-intercept is the point (4,0)\r\n" );
document.write( "That's where the line crosses the y-axis. Notice that it goes \r\n" );
document.write( "downhill as you move to the right. That tells us that the slope \"-4%2F3\" is\r\n" );
document.write( "a negative number. Notice that it rises up to 4 (the numerator of the\r\n" );
document.write( "slope) on the y-axis, and that it runs out to 3 (the denominator of the\r\n" );
document.write( "slope) on the x-axis.\r\n" );
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document.write( "Edwin
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