Area, Surface Area, and Volume
Aligned to 6.G.A.1 — Common Core State Standards for Mathematics.
What this lesson teaches
The area of a triangle is half the area of a rectangle with the same base and height, so its formula is one-half base times height. You can also find the volume of a prism and use a net, the unfolded flat version of a solid, to find its surface area.
Worked example
Find the area of a triangle with base 6 and height 4. Multiply base times height (6 times 4 = 24), then take half: 24 divided by 2 is 12.
Practice questions
- Find the area of a triangle with base 10 and height 3.
- Why is a triangle's area half of a rectangle's?
- What is a net of a shape used for?
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Área, Área de Superficie y Volumen
El área de un triángulo es la mitad del área de un rectángulo con la misma base y altura, por lo que su fórmula es la mitad de la base por la altura. También puedes encontrar el volumen de un prisma y usar una red, que es la versión plana y desplegada de un sólido, para calcular su área de superficie.
Ejemplo: Encuentra el área de un triángulo con base 6 y altura 4. Multiplica la base por la altura (6 × 4 = 24), luego toma la mitad: 24 ÷ 2 = 12.
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