Unit : – AREA & VOLUME
Chapter: – Polygons Area & volume
What students will learn in this Section
In the "Area & Volume" section of the SAT Math, students embark on a geometric journey where they not only grasp the formulas for calculating areas and volumes but also develop a profound understanding of spatial relationships. From the simplicity of finding the area of rectangles to the elegance of determining the volume of spheres, students navigate through 2-D polygons and 3-D solids with precision.
In essence, the "Area & Volume" segment not only measures a student's mathematical knowledge but also their capacity to apply these concepts creatively, fostering a deeper appreciation for the spatial intricacies that surround us in the real world.
Important Definitions & Formulae:
- Area of a Rectangle:
- The area of a rectangle is the product of its length and width: A=l×w.
- Area of a Triangle:
- The area of a triangle is half the product of its base and height: A=
× b × h.
- The area of a triangle is half the product of its base and height: A=
- Area of a Circle:
- The area of a circle is given by the formula A=π×r2, where r is the radius.
- Surface Area of a Rectangular Prism:
- The surface area of a rectangular prism is the sum of the areas of its six faces: 2lw+2lh+2wh.
- Surface Area of a Cylinder:
- The surface area of a cylinder is the sum of the areas of its two circular bases and its lateral surface: 2πr2+2πrh.
- Volume of a Rectangular Prism:
- The volume of a rectangular prism is the product of its length, width, and height: V=l×w×h.
- Volume of a Cylinder:
- The volume of a cylinder is the product of the area of its base and its height: V=πr2×h.
- Volume of a Sphere:
- The volume of a sphere is given by V=
πr3, where r is the radius.
- The volume of a sphere is given by V=
Speed Strategy
- Memorize Key Formulas:
- Memorize the formulas for area and volume of common shapes, such as rectangles, triangles, circles, cubes, cylinders, and spheres. Quick recall of these formulas saves time during the test.
- Use Approximations:
- When given numerical values in problems, consider using approximations to simplify calculations. This can help in quickly eliminating answer choices and making educated guesses.
- Look for Shortcut Techniques:
- Explore shortcut techniques for specific shapes. For example, if you know the base and height of a right-angled triangle, you can quickly find the area without going through the formula for a general triangle.
- Utilize Patterns:
- Identify patterns and relationships between different shapes. For instance, if you know the area of a square with side length "a," you can quickly find the area of a rectangle with dimensions "a" and "2a."
- Prioritize Questions:
- Quickly scan through the questions and prioritize them based on your strengths. Answer the easier or quicker questions first to maximize the number of points you can earn within the time limit.