Grade Levels: 9th Grade, 10th Grade, 11th Grade, 12th Grade,
Topics: Trigonometric Ratios
Common Core State Standard: F-TF.7, G-SRT.10, G-SRT.11,

· Triangulation

Knowledge and Skills:

· Can solve real world problems involving trigonometric ratios

Download the Teacher Guide PDF

Procedure: This activity is best done by students individually or working in teams of 2.

Distribute the handout and discuss it. Ensure that students understand what is called for.

#1: 7,325.4 + 5,253*sin (42°22’13”) = 10,865.5 m.

#2: CX = 4.410 km, BX = 3.429 km (To solve, first use law of cosines to find BC = 5.586 km. Then use law of cosines again to find angle ACB = 57°04’39”. Considering segment AC as a transversal cutting the two parallel “North” rays, angle BCX can be found to be 37°51’45”. Definitions of sine and cosine ratios are then applied to triangle BCX to find CX and BX.)

#3: (6754.3 – 5324.2)/tan(27°34’51”) = 2,737.8 m.

School-to-Career Connection: Ask a surveyor from a local USGS office or other land survey office to visit you class and discuss his or her work.