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Area and perimeter of triangles

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Intros
Lessons
  1. Introduction to Area and Perimeter of Triangles:
  2. What are the basic properties of a triangle?
  3. How do you calculate the perimeter of a triangle?
  4. How do you calculate the area of a triangle?
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Examples
Lessons
  1. Perimeter of Triangles
    Calculate the perimeter of each triangle.

    1. 2D Shapes: Area and Perimeter of Rectangles

    2. 2D Shapes: Area and Perimeter of Rectangles

    3. 2D Shapes: Area and Perimeter of Rectangles
  2. Area of Triangles
    Calculate the area of each triangle.

    1. 2D Shapes: Area and Perimeter of Rectangles

    2. 2D Shapes: Area and Perimeter of Rectangles

    3. 2D Shapes: Area and Perimeter of Rectangles
  3. Perimeter and Area of Compound Triangle Shapes
    Calculate the perimeter and area of each compound shape. Break down the complex shapes into components (triangles and rectangles) first!

    1. 2D Shapes: Area and Perimeter of Rectangles

    2. 2D Shapes: Area and Perimeter of Rectangles

    3. 2D Shapes: Area and Perimeter of Rectangles
  4. Triangles Word Problem
    The side of a skateboard ramp is a right triangle. What is the perimeter and area of the side of a skateboard ramp that has the following measurements: base=20m, height=15m, slope=25m

    2D Shapes: Area and Perimeter of Rectangles
    Topic Notes
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    In this lesson, we will learn:

    • The basic properties of the shape of the triangle
    • How to understand and calculate the perimeter of a triangle
    • How to understand and calculate the area of a triangle

    Notes:

    • A triangle is a 2D shape with 3 straight sides and 3 angles that add up to 180°
      • There are different types triangles (classified by side lengths or angle size), but it does not change the formulas for area and perimeter.

    • The perimeter is the exact distance around the shape.
      • Perimeter is a 1D (one-dimensional) quantity
        • It uses units such as meters (m, cm, mm, km), miles (mi), yards (yd), or inches and feet (in and ft)

      • For triangles, the formula is written as:
        • Ptriangle = side1 + side2 + side3

      • This formula does not change for different types of triangles

    2D Shapes: Area and Perimeter of Rectangles

    • The area is the space that is covered by the shape.
      • Area is a 2D (two-dimensional) quantity
        • It uses squared units such as square meters (m2, cm2, mm2, km2), square miles (mi2), square yards (yd2), or square inches and feet (in2 and ft2)

      • For triangles, the formula is written as:
        • Areatriangle = b × h2\large \frac{b \, \times \, h} {2}
          • Where bb is base, and hh is height

      • This formula does not change for different types of triangles, but you do need to keep in mind how to find the triangle’s height
        • The triangle’s base is any of the three straight sides
        • The triangle’s height is found by placing the chosen base as the flat bottom, and then drawing a perpendicular line from that until the highest point (vertex); it can also be called the triangle’s altitude

    2D Shapes: Area and Perimeter of Rectangles