The TI-84 device, developed by Texas Instruments, is a graphing calculator that can perform scientific calculations as well as graph, compare and analyze single or multiple graphs on a graphing palette. Although you can find the area of a curve by manually solving an equation, the TI-84 calculator can find the area underneath a curve within a matter of seconds.

Press the "Y=" button located in the top-left corner of your calculator keypad.

Type in your function into the "Y1" line and graph the function by pressing the "Graph" button located on the top-right corner of your calculator keypad.

Activate the "Calculate" menu by pressing the blue "2nd" button on your calculator and then pushing the "Trace" button, which is located left of the "Graph" button.

Scroll down to the seventh option in the "Calculate" menu. Press the "Enter" button to select the option.

Set your cursor to find the range of where you want to find the area under the normal curved graph. Press the "Left Arrow" button on your calculator until you reach the left limit. Press the "Enter" button to set the marker for the left limit.

Scroll to the right limit using the "Right Arrow" on your calculator until you reach the right limit. Press the "Enter" button to set the marker.

Press the "Enter" button on your calculator once more to calculate the area beneath the normal curve within the limits you have set in steps 5 and 6.