Skip to main content
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 48

Find the area of each triangle using the formula 𝓐 = ½ bh, and then verify that the formula 𝓐 = ½ ab sin C gives the same result.
<IMAGE>

Guida verificata passo dopo passo
1
Identify the base (b) and the height (h) of the triangle from the given image or information. The base is one side of the triangle, and the height is the perpendicular distance from the opposite vertex to this base.
Use the formula for the area of a triangle based on base and height: \(\mathcal{A} = \frac{1}{2} b h\). Substitute the values of base and height into this formula to express the area.
Next, identify two sides of the triangle, say \(a\) and \(b\), and the included angle \(C\) between them from the image or given data.
Use the formula for the area of a triangle using two sides and the included angle: \(\mathcal{A} = \frac{1}{2} a b \sin C\). Substitute the values of sides \(a\), \(b\), and angle \(C\) into this formula.
Compare the two expressions for the area obtained from the two formulas to verify that they give the same result, confirming the consistency of the area calculation methods.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Area of a Triangle Using Base and Height

The formula 𝓐 = ½ bh calculates the area of a triangle by multiplying the base length (b) by the height (h) perpendicular to that base, then dividing by two. This method requires knowing the height, which is the perpendicular distance from the base to the opposite vertex.
Video consigliato:
Percorso guidato
4:02
Calculating Area of SAS Triangles

Area of a Triangle Using Two Sides and Included Angle

The formula 𝓐 = ½ ab sin C finds the area by using two sides (a and b) and the sine of the included angle (C) between them. This approach is useful when the height is not known but two sides and the included angle are given, leveraging trigonometric relationships.
Video consigliato:
Percorso guidato
4:02
Calculating Area of SAS Triangles

Relationship Between the Two Area Formulas

Both formulas calculate the same area but use different known elements: one uses base and height, the other uses two sides and the included angle. Verifying equality involves understanding that height can be expressed as b sin C, linking the two methods through trigonometry.
Video consigliato:
Percorso guidato
4:30
Calculating Area of ASA Triangles