PROPERTIES of Triangles
In or Out?: Determine the location of the altitudes in a triangle.
Classified Information: Investigate combining triangle classifications based on length and angle measure. .
Sum It Up!: Explore the sum of interior angles of a triangle.
Shark Attack!: Find the best path from the inside of a triangle to its sides.
Remotely Interior: Compare exterior angles with remote interior angles.
Outside Looking In: Identify the sum of the exterior angles in a triangle.
To Be or Not to Be: Determine the necessary conditions to create a triangle.
Balancing the Triangular Totter: Locate the center of mass of a triangle.
Half as much may be right: Explore triangles inscribed in semicircles.
Planting Trees: Help a farmer plant four trees.
AREA and PERIMETER of Triangles
Interactive Pythagoras: Use the concept of area to demonstrate the Pythagorean Theorem
Area formulas: Investigate the areas of triangles in a variety of ways.
Triangles Inside a Trapezoid: Use the area of a triangle to transform a trapezoid into different quadrilaterals.
Prime Scalene: Find the smallest possible perimeter of a scalene triangle.
Slicing Triangles: Cut any given triangle into triangles of equal area.
Transformations of Triangles
Tiling: Tile a square patio with triangular tiles.
Constructing Isosceles Triangles: Explain how to construct isosceles triangles.
Triangles inscribed inside triangles: Explore properties of triangles constructed using the midpoint of given triangles.
Triangular numbers: Explore the sequence of triangular numbers.
SAM: Explore Symmetry with Altitudes and Medians
Puzzles that include Triangles
Hidden Triangles: Count the number of triangles in a picture.
Toothpick Transfer: Readjust a diagram to form a number of triangles.
Lining Up to Find Triangles: Draw lines to find the largest amount of triangles.
Nonoverlapping Triangles: Use three lines to form as many triangles as possible.
Pentagram Triangles: How many triangles are formed?
Counting Triangles: Determine the number of triangles in the diagram.
Magic Triangle: Place the digits 1 through 9 in the circles in a very special way.
Submit your idea for an investigation to InterMath.