Explanation Procedure used: “The steps of finding the unknown parts of an oblique triangle with given three sides are as follows: 1. Substitute the given values of the three sides into any version of the law of cosines. 2. Solve for the unknown angle in the version of the law of cosines selected in Step 1. 3. Repeat Steps 1 and 2 using a different version of the law of cosines and solving for the different angle. Or, use the angle measure found in Step 2 and find a second angle using the law of sines. 4. Find the third angle of the triangle by subtracting from 180 ° the sum of the two angles found in Steps 2 and 3.” Formula used: The law of cosines: For a triangle A B C , a 2 = b 2 + c 2 − 2 b c cos A b 2 = a 2 + c 2 − 2 a c cos B c 2 = a 2 + b 2 − 2 a b cos C Property used: Angle sum property: The sum of the three angles of the triangle is 180 ° . Calculation: It is given that the sides of the triangle are a = 26 cm , b = 28 cm , c = 32 cm . For finding ∠ A , use the formula given below. a 2 = b 2 + c 2 − 2 b c cos A a 2 − b 2 − c 2 = − 2 b c cos A Multiply both sides by 1 in order to reduce the number of negative signs and solve for cos A . − a 2 + b 2 + c 2 = 2 b c cos A − a 2 + b 2 + c 2 2 b c = cos A Substitute a = 26 cm , b = 28 cm , c = 32 cm in the above equation and find the value of A as follows: − 26 2 + 28 2 + 32 2 2 × 28 × 32 = cos A − 676 + 784 + 1024 1792 = cos A 1132 1792 = cos A 0

College Mathematics for Trades and Technologies (10th Edition) (What's New in Trade Math)

10th Edition

ISBN: 9780134690339

Author: Cheryl Cleaves, Margie Hobbs

Publisher: PEARSON

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Ratios

A ratio is a comparison between two numbers of the same kind. It represents how many times one number contains another. It also represents how small or large one number is compared to the other.

Trigonometric Ratios

Trigonometric ratios give values of trigonometric functions. It always deals with triangles that have one angle measuring 90 degrees. These triangles are right-angled. We take the ratio of sides of these triangles.

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Chapter 20.5, Problem 3E

To determine

The three angles of the triangle whose sides are a=26cm, b=28cm,c=32cm and round the angles to nearest 0.1°.

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Chapter 20.5, Problem 2E

Chapter 20.5, Problem 4E

Chapter 20 Solutions

College Mathematics for Trades and Technologies (10th Edition) (What's New in Trade Math)

Ch. 20.1 - Prob. 1LC Ch. 20.1 - Prob. 1E Ch. 20.1 - Prob. 2E Ch. 20.1 - Prob. 3E Ch. 20.1 - Prob. 4E Ch. 20.1 - Prob. 5E Ch. 20.1 - Prob. 6E Ch. 20.1 - Prob. 7E Ch. 20.1 - Prob. 8E Ch. 20.1 - Prob. 9E

Ch. 20.1 - Prob. 10E Ch. 20.1 - Prob. 11E Ch. 20.1 - Prob. 12E Ch. 20.1 - Prob. 13E Ch. 20.1 - Prob. 14E Ch. 20.1 - Prob. 15E Ch. 20.1 - Prob. 16E Ch. 20.1 - Prob. 17E Ch. 20.1 - Prob. 18E Ch. 20.1 - Prob. 19E Ch. 20.1 - Prob. 20E Ch. 20.1 - Prob. 21E Ch. 20.1 - Prob. 22E Ch. 20.1 - Prob. 23E Ch. 20.1 - Prob. 24E Ch. 20.1 - Prob. 25E Ch. 20.1 - Prob. 26E Ch. 20.1 - Prob. 27E Ch. 20.1 - Prob. 28E Ch. 20.1 - Prob. 29E Ch. 20.1 - Prob. 30E Ch. 20.1 - Prob. 31E Ch. 20.1 - Prob. 32E Ch. 20.2 - Prob. 1LC Ch. 20.2 - Prob. 2LC Ch. 20.2 - Prob. 1E Ch. 20.2 - Prob. 2E Ch. 20.2 - Prob. 3E Ch. 20.2 - Prob. 4E Ch. 20.2 - Prob. 5E Ch. 20.2 - Prob. 6E Ch. 20.2 - Prob. 7E Ch. 20.2 - Prob. 8E Ch. 20.2 - Prob. 9E Ch. 20.2 - Prob. 10E Ch. 20.2 - Prob. 11E Ch. 20.2 - Prob. 12E Ch. 20.2 - Prob. 13E Ch. 20.2 - Prob. 14E Ch. 20.2 - Prob. 15E Ch. 20.2 - Prob. 16E Ch. 20.2 - Prob. 17E Ch. 20.2 - Prob. 18E Ch. 20.2 - Prob. 19E Ch. 20.2 - Prob. 20E Ch. 20.2 - Prob. 21E Ch. 20.2 - Prob. 22E Ch. 20.2 - Prob. 23E Ch. 20.2 - Prob. 24E Ch. 20.2 - Prob. 25E Ch. 20.3 - Prob. 1LC Ch. 20.3 - Prob. 2LC Ch. 20.3 - Evaluate. Ch. 20.3 - Prob. 4LC Ch. 20.3 - Prob. 1E Ch. 20.3 - Prob. 2E Ch. 20.3 - Prob. 3E Ch. 20.3 - Prob. 4E Ch. 20.3 - Prob. 5E Ch. 20.3 - Prob. 6E Ch. 20.3 - Prob. 7E Ch. 20.3 - Prob. 8E Ch. 20.3 - Prob. 9E Ch. 20.3 - Prob. 10E Ch. 20.3 - Prob. 11E Ch. 20.3 - Prob. 12E Ch. 20.3 - Prob. 13E Ch. 20.3 - Prob. 14E Ch. 20.3 - Prob. 15E Ch. 20.3 - Prob. 16E Ch. 20.3 - Prob. 17E Ch. 20.3 - Prob. 18E Ch. 20.3 - Prob. 19E Ch. 20.3 - Prob. 20E Ch. 20.3 - Prob. 21E Ch. 20.3 - Prob. 22E Ch. 20.3 - Prob. 23E Ch. 20.3 - Prob. 24E Ch. 20.3 - Prob. 25E Ch. 20.3 - Prob. 26E Ch. 20.3 - Prob. 27E Ch. 20.3 - Prob. 28E Ch. 20.3 - Prob. 29E Ch. 20.3 - Prob. 30E Ch. 20.3 - Prob. 31E Ch. 20.3 - Prob. 32E Ch. 20.3 - Prob. 33E Ch. 20.3 - Prob. 34E Ch. 20.3 - Prob. 35E Ch. 20.3 - Prob. 36E Ch. 20.3 - Prob. 37E Ch. 20.3 - Prob. 38E Ch. 20.3 - Prob. 39E Ch. 20.3 - Prob. 40E Ch. 20.3 - Prob. 41E Ch. 20.3 - Prob. 42E Ch. 20.3 - Prob. 43E Ch. 20.3 - Prob. 44E Ch. 20.3 - Prob. 45E Ch. 20.3 - Prob. 46E Ch. 20.3 - Prob. 47E Ch. 20.4 - Evaluate to four significant digits. Ch. 20.4 - Prob. 1E Ch. 20.4 - Prob. 2E Ch. 20.4 - Prob. 3E Ch. 20.4 - Prob. 4E Ch. 20.4 - Prob. 5E Ch. 20.4 - Prob. 6E Ch. 20.4 - Prob. 7E Ch. 20.4 - Prob. 8E Ch. 20.4 - Prob. 9E Ch. 20.4 - Prob. 10E Ch. 20.4 - Prob. 11E Ch. 20.4 - Prob. 12E Ch. 20.4 - Prob. 13E Ch. 20.4 - Prob. 14E Ch. 20.4 - Prob. 15E Ch. 20.4 - Prob. 16E Ch. 20.4 - Prob. 17E Ch. 20.4 - Prob. 18E Ch. 20.4 - Prob. 19E Ch. 20.4 - Prob. 20E Ch. 20.4 - Prob. 21E Ch. 20.4 - Prob. 22E Ch. 20.5 - Prob. 1LC Ch. 20.5 - Prob. 1E Ch. 20.5 - Prob. 2E Ch. 20.5 - Prob. 3E Ch. 20.5 - Prob. 4E Ch. 20.5 - Prob. 5E Ch. 20.5 - Find the three angles of each triangle. Round...Ch. 20.5 - Prob. 7E Ch. 20.5 - Prob. 8E Ch. 20.5 - Prob. 9E Ch. 20.5 - Prob. 10E Ch. 20.5 - CON A hill is inclined 20° to the horizontal. A...Ch. 20.5 - Prob. 12E Ch. 20 - Prob. 1RE Ch. 20 - Prob. 2RE Ch. 20 - Prob. 3RE Ch. 20 - Prob. 4RE Ch. 20 - Prob. 5RE Ch. 20 - Prob. 6RE Ch. 20 - Prob. 7RE Ch. 20 - Prob. 8RE Ch. 20 - Prob. 9RE Ch. 20 - Prob. 10RE Ch. 20 - Prob. 11RE Ch. 20 - Prob. 12RE Ch. 20 - Prob. 13RE Ch. 20 - Prob. 14RE Ch. 20 - Prob. 15RE Ch. 20 - Prob. 16RE Ch. 20 - Prob. 17RE Ch. 20 - Prob. 18RE Ch. 20 - Prob. 19RE Ch. 20 - Prob. 20RE Ch. 20 - Prob. 21RE Ch. 20 - Prob. 22RE Ch. 20 - Prob. 23RE Ch. 20 - Prob. 24RE Ch. 20 - Prob. 25RE Ch. 20 - Prob. 26RE Ch. 20 - Prob. 27RE Ch. 20 - Prob. 28RE Ch. 20 - Prob. 29RE Ch. 20 - Prob. 30RE Ch. 20 - Prob. 31RE Ch. 20 - Prob. 32RE Ch. 20 - Prob. 33RE Ch. 20 - Prob. 34RE Ch. 20 - Prob. 35RE Ch. 20 - Prob. 36RE Ch. 20 - Prob. 37RE Ch. 20 - Prob. 38RE Ch. 20 - Prob. 39RE Ch. 20 - Prob. 40RE Ch. 20 - Solve the triangles. If a triangle has two...Ch. 20 - Prob. 42RE Ch. 20 - Prob. 43RE Ch. 20 - Prob. 44RE Ch. 20 - Prob. 45RE Ch. 20 - Prob. 46RE Ch. 20 - Prob. 47RE Ch. 20 - Prob. 48RE Ch. 20 - Solve the exercises. Round sides to four...Ch. 20 - Prob. 50RE Ch. 20 - Prob. 51RE Ch. 20 - Prob. 1CA Ch. 20 - Prob. 2CA Ch. 20 - Prob. 3CA Ch. 20 - Prob. 4CA Ch. 20 - Prob. 5CA Ch. 20 - Prob. 6CA Ch. 20 - Prob. 7CA Ch. 20 - Prob. 8CA Ch. 20 - Prob. 9CA Ch. 20 - Prob. 10CA Ch. 20 - Prob. 11CA Ch. 20 - Prob. 12CA Ch. 20 - Prob. 13CA Ch. 20 - Prob. 14CA Ch. 20 - Prob. 15CA Ch. 20 - Prob. 16CA Ch. 20 - Prob. 1PT Ch. 20 - Prob. 2PT Ch. 20 - Prob. 3PT Ch. 20 - Prob. 4PT Ch. 20 - Prob. 5PT Ch. 20 - Prob. 6PT Ch. 20 - Prob. 7PT Ch. 20 - Prob. 8PT Ch. 20 - Prob. 9PT Ch. 20 - Prob. 10PT Ch. 20 - Prob. 11PT Ch. 20 - Prob. 12PT Ch. 20 - Prob. 13PT Ch. 20 - Prob. 14PT Ch. 20 - Prob. 15PT Ch. 20 - Prob. 16PT Ch. 20 - Prob. 17PT Ch. 20 - Prob. 18PT Ch. 20 - Prob. 19PT Ch. 20 - Prob. 20PT Ch. 20 - Prob. 21PT Ch. 20 - A rod 11 cm long joins a crank 20 cm long to form...Ch. 20 - Prob. 23PT Ch. 20 - Prob. 24PT Ch. 20 - Prob. 1CPT Ch. 20 - Prob. 2CPT Ch. 20 - Prob. 3CPT Ch. 20 - Prob. 4CPT Ch. 20 - Prob. 5CPT Ch. 20 - Prob. 6CPT Ch. 20 - Prob. 7CPT Ch. 20 - Prob. 8CPT Ch. 20 - Prob. 9CPT Ch. 20 - Prob. 10CPT Ch. 20 - Prob. 11CPT Ch. 20 - Prob. 12CPT Ch. 20 - Prob. 13CPT Ch. 20 - Find the resultant vector of the vectors that have...Ch. 20 - Prob. 15CPT Ch. 20 - Prob. 16CPT Ch. 20 - Prob. 17CPT Ch. 20 - Prob. 18CPT Ch. 20 - Prob. 19CPT Ch. 20 - Prob. 20CPT

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