document.write( "Question 19328: can you tell me how to graph the points of y=3x-1. I get confused on the -1 part. is that negative 1 or minus 1. thank you \n" ); document.write( "
Algebra.Com's Answer #9349 by mmm4444bot(95)\"\" \"About 
You can put this solution on YOUR website!
Hello There:\r
\n" ); document.write( "\n" ); document.write( "As far as the -1 goes, there are two ways of looking at it. It is subtracting a positive 1, or you can say that it is adding a negative 1.\r
\n" ); document.write( "\n" ); document.write( "y = 3*x - (+1)\r
\n" ); document.write( "\n" ); document.write( "y = 3*x + (-1)\r
\n" ); document.write( "\n" ); document.write( "Both interpretations mean the same thing.\r
\n" ); document.write( "\n" ); document.write( "I tend to see it as subtracting a positive 1.\r
\n" ); document.write( "\n" ); document.write( "To graph the solutions to this equation (a line), we need to find the coordinants of two points that satisfy the equation. Then it's just a matter of plotting these two points and drawing a straight line through them.\r
\n" ); document.write( "\n" ); document.write( "Two easy points to find are the x- and y-intercepts. The x-intercept occurs when y is zero, and the y-intercept occurs when x is zero.\r
\n" ); document.write( "\n" ); document.write( "Let's find the y-intercept first. Set x equal to zero.\r
\n" ); document.write( "\n" ); document.write( "y = 3*(0) - 1\r
\n" ); document.write( "\n" ); document.write( "y = -1\r
\n" ); document.write( "\n" ); document.write( "The y-intercept is (0, -1)\r
\n" ); document.write( "\n" ); document.write( "Now we find the x-intercept. Set y equal to zero.\r
\n" ); document.write( "\n" ); document.write( "0 = 3*x - 1\r
\n" ); document.write( "\n" ); document.write( "Add 1 to both sides.\r
\n" ); document.write( "\n" ); document.write( "0 + 1 = 3*x + 1 - 1\r
\n" ); document.write( "\n" ); document.write( "3*x = 1\r
\n" ); document.write( "\n" ); document.write( "Divide both sides by 3.\r
\n" ); document.write( "\n" ); document.write( "(3/3)*x = 1/3\r
\n" ); document.write( "\n" ); document.write( "x = 1/3\r
\n" ); document.write( "\n" ); document.write( "The x-intercept is (1/3, 0).\r
\n" ); document.write( "\n" ); document.write( "If you find that these two points are too close together to draw an accurate line for your graph, then you can just pick some values for x and substitute them into the equation to get other solutions.\r
\n" ); document.write( "\n" ); document.write( "For example, let's choose 10 for x.\r
\n" ); document.write( "\n" ); document.write( "y = 3*(10) - 1\r
\n" ); document.write( "\n" ); document.write( "y = 30 - 1\r
\n" ); document.write( "\n" ); document.write( "y = 29\r
\n" ); document.write( "\n" ); document.write( "So, the point (10, 29) is also a point on the line.\r
\n" ); document.write( "\n" ); document.write( "~ Mark\r
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