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 Question from tyler, a student: y=2x+4 graph

Hi Tyler,

I would use a table. Substitute various values for $x$ and calculate the corresponding values of $y.$ Choose points where the arithmetic is easy for example $x = 0, 1, 2, -1, -2,\cdot\cdot\cdot.$ Here is a start for a table

x y
0 4
1 6
-1 2
2 ?
-2 ?

I substituted $x = 0$ into $y = 2x + 4$ and got $y = 4.$
I substituted $x = 1$ into $y = 2x + 4$ and got $y = 6.$
I substituted $x = -1$ into $y = 2x + 4$ and got $y = 2.$

Complete the table for a few more row. Next plot the points in the plane, $(0, 4), (1, 6), (-1, 2)$ and so on. If you have drawn an accurate diagram you can use a straight edge to see that they all lie on a line. This line is the graph.

Penny

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