document.write( "Question 69260: Can you please help with this, I do not know what book it came from.There are actually squares around these numbers to form a table.
\n" ); document.write( " Take a look at the table below and write out an equation for f(x).\r
\n" ); document.write( "\n" ); document.write( "x -2 -1 0 1 2
\n" ); document.write( "f(x) -5 -2 1 4 7 \n" ); document.write( "
Algebra.Com's Answer #49325 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
f(x) = y; make the table look like this:
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\n" ); document.write( " x | y
\n" ); document.write( "-------
\n" ); document.write( "-2 |-5
\n" ); document.write( "-1 |-2
\n" ); document.write( " 0 |+1
\n" ); document.write( "+1 |+4
\n" ); document.write( "+2 |+7
\n" ); document.write( ":
\n" ); document.write( "Look at this table and you can tell that it is a linear equation, for each unit
\n" ); document.write( "change in x, there is a 3 unit change in y, so really we only need 2 x/y sets
\n" ); document.write( "to write a linear equation. Find the slope using the last two coordinates in
\n" ); document.write( "the table: x1 = 2; y1 = 4; x2 = 2; y2 = 7
\n" ); document.write( ":
\n" ); document.write( "Remember the slope (m) equation: m = (y2 - y1)/(x2 - x1)
\n" ); document.write( ":
\n" ); document.write( "In our problem: m = (7 - 4)/(2 -1)
\n" ); document.write( "m = 3/1 or just +3
\n" ); document.write( ":
\n" ); document.write( "Use the point slope equation: y - y1 = m(x-x1)
\n" ); document.write( "y - 4 = 3(x - 1)
\n" ); document.write( "y - 4 = 3x - 3
\n" ); document.write( "y = 3x - 3 + 4
\n" ); document.write( "y = 3x + 1
\n" ); document.write( "Or
\n" ); document.write( "f(x) = 3x + 1
\n" ); document.write( ":
\n" ); document.write( "The graph of this equation looks like this:
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-4%2C+4%2C+-8%2C+10%2C+3x+%2B+1%29+\"
\n" ); document.write( ":
\n" ); document.write( "you can see that all the coordinates in the table are on the graph
\n" ); document.write( "Also you can substitute each value for x in the equation and solve for y to
\n" ); document.write( "see if it corresponds to the y value in the table.
\n" ); document.write( ":
\n" ); document.write( "For example when x = -2:
\n" ); document.write( "y = 3(-2) + 1;
\n" ); document.write( "y = -6 + 1;
\n" ); document.write( "y = -5, the given value in the table
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\n" ); document.write( "Did this help you understand this now? Any questions? \n" ); document.write( "
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