Education Technology

• ##### Device
• TI-84 Plus
• TI-84 Plus CE Family
• ##### Software

TI Connect™ CE

# SA and NT: Ain't No River Wide Enough

by Texas Instruments

#### Overview

Students simulate the process a surveyor would use to measure the width of a river by measuring length on one side of the river and angles formed by various reference points.

#### Key Steps

• Students use the RIVER data in Cabri™ Jr. to investigate the scenario of a team building a bridge over a river. Students work as a team to find some ideas on ways to measure the width indirectly without crossing the river.

• Students will use points to represent stakes, and will draw a triangle between two stakes on one side of the river and a rock on the far side. They should see that the triangle is a not a right triangle, and they will not be able to use the Pythagorean Theorem.

• Students move forward to prove the Law of Sines using the LAWSINES data in Cabri Jr.® Students will relate the lengths of the sides of a triangle to its angles.