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Ch. 7 - Applications of Trigonometry and Vectors
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161, 9780135440780, 9780136881117, 9780135440827, 9780135924891Non è quello che usi tu?Cambia libro di testo
Capitolo 8, Problema 55

Find the area of each triangle ABC.


A = 56.80°, b = 32.67 in., c = 52.89 in.

Guida verificata passo dopo passo
1
Identify the given elements: angle \(A = 56.80^\circ\), side \(b = 32.67\) inches, and side \(c = 52.89\) inches. We need to find the area of triangle \(ABC\).
Recall the formula for the area of a triangle when two sides and the included angle are known: \(\text{Area} = \frac{1}{2}bc \sin A\).
Substitute the known values into the formula: \(\text{Area} = \frac{1}{2} \times 32.67 \times 52.89 \times \sin(56.80^\circ)\).
Calculate \(\sin(56.80^\circ)\) using a calculator or trigonometric table, ensuring your calculator is in degree mode.
Multiply the values together to find the area: first multiply the two sides, then multiply by the sine of the angle, and finally multiply by \(\frac{1}{2}\).

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