##### TI-Nspire For Dummies

Calculations can be used to make sense of the measurements that were taken. The TI-Nspire Attach feature is a handy way to display the results of the calculations and measurements. You can use these tools to prove that two angles that form a linear pair are supplementary.

Follow these steps to perform a calculation:

1. Place some text for your calculation. Move your cursor to an open space, right-click ([CTRL][MENU]), and choose Text. Type a+b and then press [ENTER].

2. Right-click ([CTRL][MENU]) the text, choose Calculate, [CLICK] one of the angle measures, and then [CLICK] the other angle measure. Press [ENTER] to anchor the calculation.

See the second screen.

3. To lay down more text, right-click, [CTRL][MENU]→Text. Press

(degree symbol). Press [ENTER] to anchor the text. Repeat two more times to give [+] and [=] a text box of their own.

4. Work right to left and attach each piece of the equation to the piece before it. Right-click ([CTRL][MENU]) degree symbol, choose Attach, and [CLICK] the right side of the 180.

Now, right-click 180 degrees and attach it to the = sign. Keep working backward until the equation is together in one attached piece! See the third screen.

The Graphs and the Geometry applications are approximate environments. As a result, you may occasionally get a calculation or result that is not what you expect. For example, if you move the point to form a 0˚ angle, TI-Nspire displays 1.21Å-6˚, instead of 0˚. This is scientific notation for the number 0.00000121, which is extremely close to zero. Consider these small noise values to be zero.

Jeff McCalla teaches Algebra 2 and Pre-Calculus at St. Mary's Episcopal School in Memphis. He is a T3 instructor for Texas Instruments and co- founder of the TI-Nspire SuperUser group. Steve Ouellette wrote the first edition of TI-Nspire For Dummies as well as CliffsNotes® Guide to TI-Nspire.