   SEARCH HOME Math Central Quandaries & Queries  Question from jacinda, a student: how to make a chart for y=mx+b Hi Jacinda,

I assume that you have been given specific values for $m$ and $b.$ I'm going to use $m = -2$ and $b = 5$ so my equation is $y = -2 x + 5.$ I would then set up a table or chart that looks like

x y

$y = -2 x + 5$

Now substitute some values for $x$ and evaluate $y = -2 x + 5$ to determine $y.$ I would start with small numbers to make the arithmetic easy. For example when $x = 0$ then $y = -2 x + 5 = -2 \times 0 + 5 = 5.$ Put this pair of numbers $(0, 5)$ into the chart.

x y
0 5

$y = -2 x + 5$

Now try another value for $x,$ say $x = 1.$ this gives $y = -2x + 5 = -2 \times 1 + 5 = 3.$ Put the pair $(1, 3)$ into the table.

x y
0 5
1 3

$y = -2 x + 5$

Do it again with $x = -1$ to give $y = -2x + 5 = -2 \times -1 + 5 = 7.$ Put the pair $(-1, 7)$ into the table.

x y
0 5
1 3
-1 7

$y = -2 x + 5$

Continue for as many values of $x$ as you feel is necessary.

Penny     Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.