PYRAMIDS - Solid Geometry - SOLID AND COORDINATE GEOMETRY - SAT SUBJECT TEST MATH LEVEL 1

SAT SUBJECT TEST MATH LEVEL 1

SOLID AND COORDINATE GEOMETRY

CHAPTER 12 Solid Geometry

PYRAMIDS

A pyramid is very similar to a cone. The difference is that the base of a pyramid is a polygon, not a circle. If there is a question concerning pyramids on the Math 1 test you take, the polygonal base will almost surely be a square or a triangle.

The formula for the volume of a pyramid, which is one of the five formulas in the “Reference Information” box on the Math 1 test, is given in KEY FACT K7.

Key Fact K7

The formula for the volume of a pyramid is Bh , where B is the area of the base and h is the height.

Remember

The formula in KEY FACT K7 is listed in the Reference Information box on the first page of every Math 1 test.

Note that since the area of the circular base of a cone is r2, this formula applies to cones, as well.

EXAMPLE 6: What is the volume of a pyramid whose base is a square of side 3 feet and whose height is 6 feet?

Sketch the pyramid and use the formula given in KEY FACT K7.

The area of the square base is 9 square feet, and so cubic feet.