# How  do I create a T-chart  for f(x)=2(1/2)^x-5

justaguide | Certified Educator

The T-chart for a function y = f(x) consists of two columns, the first has random values of x and the other has corresponding values of f(x) for each of the values of x.

For `f(x) = 2*(1/2)^x - 5` , the following is one of the T-charts that can be created:

x  | f(x) = `2*(1/2)^x - 5`

-3 | 11

-2 | 3

-1 |  -1

0  |  -3

1  | -4

2  | -4.5

3  | -4.75

steveschoen | Certified Educator

Any values for x will due.  For different functions and numbers, some numbers will work better than others.  However, any numbers will due.  That's part of the greatness behind it; you have the power.  Just pick a number for x, plug it into f(x), see what f(x) would equal.

rachellopez | Student

T charts have two columns, one for x and one for y. In this case you can use any numbers you want for x and just substitute the values you choose for x in the equation to get y.

For example, if you chose 1 for your x value you would get f(x)=2(1/2)^1-5. In the t chart x=1 and y would equal ``-4. It will end up looking something like this

x        y

1        -4

2        -4.5

3        -4.75

and so on. Hope this helps :)

nav1996 | Student

A T-chart is a very simple tool that can be used to estimate the shape of a graph. In order to create a T-chart for an equation, the equation must be a function, meaning that each x-value must correspond to only one y-value.

To create a T-chart, all you have to do is choose a set of x-values and plug them into the equation to find the corresponding y-value. Here is a sample of a T-chart for x-values from 0 to 3.

x-value | y-value

0 | -3

1 | -4

2 | -4.5

3 | -4.75

chrisyhsun | Student

Essentially, you can make a T-chart however you want. The T-chart isn't a strictly necessary step; it's merely a tool to help you more easily graph the function.

As the educator answers mentioned, you can pick any x-values you want for one side of the chart, then fill in their corresponding y-values (found by plugging in the x-values). I would suggest picking x-values that are easy to plug in or give nice answers - no need to complicate matters!

Hope this helps!