Making Measurements

With a triangle drawn on your screen, the next step is to measure its area. Choose option 2: Area from the Measurement menu (b8) and then move the cursor to one of the sides of the triangle. The triangle label and the pointing-finger icon appear together with a calculated area

in the background. Click to confirm the choice of the triangle, then move your cursor to where you want the measurement displayed then click again to show the measurement and finally press d to remove the icon from the top left corner.

The area is now displayed (to the number of significant figures set in the Graphs & Geometry settings ~722).

Remember you can place the cursor over the calculated value (you should see the open-hand icon) and press + or - several times. The effect is to reduce the number of displayed decimal places. This feature can be applied to any numbers on the screen in either the Graph or Geometry application.

First Steps with TI-Nspire

Tutorial 5: Geometry

Measurement menu

Notice the range of other

possible measurements available

from this menu.

Variables and Text

 

There are two ways to make it clear that the measurement at

 

the bottom of the screen represents an area. One method is to

 

simply add some text alongside the measurement. However,

 

a more powerful method is to allocate the measurement to a

 

variable and display the variable name alongside it. To do this:

 

• move the cursor over the measurement (you will see the

 

open-hand icon;

 

• press h and choose option 1: Store Var (Alternatively

 

press /h)

Storing the measurement as a variable

• use the alphabetic keys to give the variable the name

 

area”. Press ·.

 

This variable may now be used on other pages of the document. For example, if you move to a Calculator page, type and enter area, the current value of the area will be used.

© 2012 Texas Instruments Education Technology

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Texas Instruments TINSPIRECX manual Making Measurements, Variables and Text, Measurement menu