document.write( "Question 887716: What’s the equation of a line that passes through points (0, -1) and (2, 3)? \r
\n" ); document.write( "\n" ); document.write( "Please help me with step by step on this.
\n" ); document.write( "Thank you
\n" ); document.write( "

Algebra.Com's Answer #536813 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "First let's find the slope of the line through the points and \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Note: is the first point . So this means that \"x%5B1%5D=0\" and \"y%5B1%5D=-1\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=2\" and \"y%5B2%5D=3\".\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\" Start with the slope formula.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=%283--1%29%2F%282-0%29\" Plug in \"y%5B2%5D=3\", \"y%5B1%5D=-1\", \"x%5B2%5D=2\", and \"x%5B1%5D=0\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=%284%29%2F%282-0%29\" Subtract \"-1\" from \"3\" to get \"4\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=%284%29%2F%282%29\" Subtract \"0\" from \"2\" to get \"2\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=2\" Reduce\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the slope of the line that goes through the points and is \"m=2\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now let's use the point slope formula:\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y-y%5B1%5D=m%28x-x%5B1%5D%29\" Start with the point slope formula\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y--1=2%28x-0%29\" Plug in \"m=2\", \"x%5B1%5D=0\", and \"y%5B1%5D=-1\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y%2B1=2%28x-0%29\" Rewrite \"y--1\" as \"y%2B1\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y%2B1=2x%2B2%28-0%29\" Distribute\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y%2B1=2x%2B0\" Multiply\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y=2x%2B0-1\" Subtract 1 from both sides. \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y=2x-1\" Combine like terms. \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=2x-1\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=2x-1\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=2x-1\" through the points and \r
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );