August 25, 2009

Learn how to use different height lines to find area of a triangle

- Mathematics > General
- Mathematics > Geometry

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Find the area of right triangles, other triangles, special quadrilaterals, and polygons by composing into rectangles or decomposing into triangles and other shapes; apply these techniques in the context of solving real-world and mathematical problems.

(+) Derive the formula A = 1/2 ab sin(C) for the area of a triangle by drawing an auxiliary line from a vertex perpendicular to the opposite side.

Use coordinates to compute perimeters of polygons and areas of triangles and rectangles, e.g., using the distance formula.?

model area formulas for parallelograms, trapezoids, and triangles by decomposing and rearranging parts of these shapes;

write equations that represent problems related to the area of rectangles, parallelograms, trapezoids, and triangles and volume of right rectangular prisms where dimensions are positive rational numbers; and

determine solutions for problems involving the area of rectangles, parallelograms, trapezoids, and triangles and volume of right rectangular prisms where dimensions are positive rational numbers.