Question 547006
let's use an example
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Say your told to graph f(x) = x^2 - 8x + 12
on a graph, f(x) = y, therefore rewrite the equation to
y = x^2 - 8x + 12
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When they say f(2), they mean find the value of y when x=2
When they say f(1), they mean find the value of y when x=1
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find the points on the graph from +1 to + 7
f(1); x=1, replace x with 1 and find y
y = 1^2 - 8(1) + 12
y = 1 - 8 + 12
y = 5
The ordered x,y pair: 1, 5
:
do the same with f(3); x=3
y = 3^2 - 8(3) + 12
y = 9 - 24 + 12
y = -3
The ordered pair: 3, -3
We can make a table from doing this, doing the same for each value of x, find y
 x | y
-------
 1 | +5
 2 | 0 
 3 | -3
 4 | -4
 5 | -3
 6 | 0
 7 | +5
 choose the values for x, in the range that will give a meaningful graph, graph each point.
this equation should look like this
{{{ graph( 300, 200, -4, 10, -10, 14, x^2-8x+12) }}}
Look at the table and you can see that it agrees with the x,y value on the graph
Just remember that in graphing, f(x) just means y
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Did this help, any questions?