Table of contents
- 0. Fundamental Concepts of Algebra3h 29m
- 1. Equations and Inequalities3h 27m
- 2. Graphs1h 43m
- 3. Functions & Graphs2h 17m
- 4. Polynomial Functions1h 54m
- 5. Rational Functions1h 23m
- 6. Exponential and Logarithmic Functions2h 28m
- 7. Measuring Angles40m
- 8. Trigonometric Functions on Right Triangles2h 5m
- 9. Unit Circle1h 19m
- 10. Graphing Trigonometric Functions1h 19m
- 11. Inverse Trigonometric Functions and Basic Trig Equations1h 41m
- 12. Trigonometric Identities 2h 34m
- 13. Non-Right Triangles1h 38m
- 14. Vectors2h 25m
- 15. Polar Equations2h 5m
- 16. Parametric Equations1h 6m
- 17. Graphing Complex Numbers1h 7m
- 18. Systems of Equations and Matrices3h 6m
- 19. Conic Sections2h 36m
- 20. Sequences, Series & Induction1h 15m
- 21. Combinatorics and Probability1h 45m
- 22. Limits & Continuity1h 49m
- 23. Intro to Derivatives & Area Under the Curve2h 9m
8. Trigonometric Functions on Right Triangles
Solving Right Triangles
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Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
A right triangle with an angle of 31° has a hypotenuse of 10. Calculate the side of the triangle opposite to the 31° angle (y), and the side adjacent to the 31° angle (x). Round your answer to 3 decimal places.
A
x=5.150,y=8.572
B
x=8.572,y=5.150
C
y=5.000,x=8.660
D
y=8.660,x=5.000

1
Identify the given information: a right triangle with an angle of 31° and a hypotenuse of 10.
Use the sine function to find the side opposite the 31° angle. The sine of an angle in a right triangle is the ratio of the length of the opposite side to the hypotenuse. Set up the equation: sin(31°) = opposite / 10.
Solve for the opposite side (y) by multiplying both sides of the equation by 10: y = 10 * sin(31°).
Use the cosine function to find the side adjacent to the 31° angle. The cosine of an angle in a right triangle is the ratio of the length of the adjacent side to the hypotenuse. Set up the equation: cos(31°) = adjacent / 10.
Solve for the adjacent side (x) by multiplying both sides of the equation by 10: x = 10 * cos(31°).
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