document.write( "Question 14435: I need to find an equation for a line whose points are (3,6) and (5,7). I have found the slope which is 1/2 and know the equation should be in the form of Y= mx + b. But I don't understand how to calculate the value of b. Please help. \n" ); document.write( "

Algebra.Com's Answer #7229 by atif.muhammad(135) $\"\"$ $\"About$

You can put this solution on YOUR website!

There is a formula for your problem\r\n" );
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document.write( "(y-y1) = m(x-x1)\r\n" );
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document.write( "where:\r\n" );
document.write( "y = your y variable\r\n" );
document.write( "y1 = your known y-value\r\n" );
document.write( "m = gradient\r\n" );
document.write( "x = your x variable\r\n" );
document.write( "x1 = your known x-value\r\n" );
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document.write( "lets take one of the co-ordinates: (3,6)\r\n" );
document.write( "you say the the gradient is 1/2.\r\n" );
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document.write( "Therefore, by subsituting in the value to my formula, I get:\r\n" );
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document.write( "(y-y1) = m(x-x1)\r\n" );
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document.write( "y = y\r\n" );
document.write( "y1 = 6\r\n" );
document.write( "m = 1/2\r\n" );
document.write( "x = x\r\n" );
document.write( "x1 = 3\r\n" );
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document.write( "(y-6) = 1/2 * (x-3)\r\n" );
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document.write( "y-6 = (x/2) - 3/2\r\n" );
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document.write( "y = (x/2) - 3/2 + 6\r\n" );
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document.write( "y = (x/2) + 9/2\r\n" );
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document.write( "y = 0.5x + 4.5\r\n" );
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