Area of Three Triangles

Directions: Use the integers 2 to 10, at most one time each, as lengths of individual sides to form three triangles. What is the smallest total area of the three triangles you can create? What is the largest?

Hint

For Geometry: You will need to give them Heron’s formula if they don’t know it.
For Trig: “How can we find the area of a triangle if we know all three sides but no angles?”
In general: “How can I make sure all three are triangles?”

Answer

Minimum Area: 2-9-10, 3-6-7 and 4-5-8
Maximum Area: 2-3-4, 5-6-7, 8-9-10

Source: Dan Wulf

Use This Problem

Embedded problems let you easily add Open Middle problems into your Canvas assignments, Google Classroom, and more. Customize which elements are shown, and watch it update live before adding it anywhere.

Mode

Customization

Add to Platform

Check Also

Composite Volume

Directions: Using the digits 0 to 9, at most one time each, place a digit …

4 comments

  1. Why do you have multiple “minimum” area answers? And multiple “maximum”?

    And why was 2, 3, 4 included…

    These answers don’t make sense to me, am I missing something?

    • I am reading the answers as the measurements of the three sides. We need to find three sets of three numbers. 2, 3, 4 are valid from the question

  2. I am so confused on how to do area of a triangle? HELP

  3. It seems you would be allowed to “reuse” the length of a side for a second triangle. For example, use the length of 10 in three triangles if you allowed the triangles to overlap.

Leave a Reply

Your email address will not be published. Required fields are marked *