TrigonometryPYTHAGOREAN THEOREMRev. 0Page 1MA-04Figure 1 TrianglePYTHAGOREAN THEOREMThis chapter covers right triangles and solving for unknowns usingthe Pythagorean theorem.EO 1.1Given a problem, APPLY the Pythagorean theorem tosolve for the unknown values of a right triangle.Trigonometry is the branch of mathematics that is the study of angles and the relationshipbetween angles and the lines that form them. Trigonometry is used in Classical Physics andElectrical Science to analyze many physical phenomena. Engineers and operators use thisbranch of mathematics to solve problems encountered in the classroom and on the job. Themost important application of trigonometry is the solution of problems involving triangles,particularly right triangles. Trigonometry is one of the most useful branches of mathematics. It is used to indirectlymeasure distances which are difficult to measure directly. For example, the height of a flagpoleor the distance across a river can be measured using trigonometry.As shown in Figure 1 below, a triangle is a plane figureformed using straight line segments (AB, BC, CA) toconnect three points (A, B, C) that are not in a straightline.The sum of the measures of the three interiorangles (a', b', c') is 180- , and the sum of the lengths ofany two sides is always greater than or equal to thethird.PythagoreanTheoremThe Pythagorean theorem is a tool that can be used tosolve for unknown values on right triangles. In order touse the Pythagorean theorem, a term must be defined.The term hypotenuse is used to describe the side of aright triangle opposite the right angle. Line segment Cis the hypotenuse of the triangle in Figure 1.The Pythagorean theorem states that in any right triangle, the square of the length of thehypotenuse equals the sum of the squares of the lengths of the other two sides.This may be written as c = a + b or .(4-1)22 2