Lesson objective: Apply their understanding of the Triangle Inequality Theorem to determine an efficient design for a kitchen.

This lesson provides an opportunity for students to apply their knowledge and understanding the the sum of any two lengths of a triangle must be greater than the length of the third side to a real-life situation. Students are asked to consider three possible locations for a stove in a kitchen so that an efficient "kitchen work triangle" can be formed.

Key Concept students will use:

Skills students will use:

- the Triangle Inequality Theorem to decide an unknown measure, the distance from the sink to the stove in a kitchen.
- when given two sides of a triangle, students will determine the range of acceptable values for the length of the third side of the triangle.

Students engage in Mathematical Practice #3 (construct viable arguments and critique the reasoning of others) as they decide the best location for a stove that will produce the most efficient design for a kitchen.

**Key vocabulary: **

- acute triangle
- angle
- base angle
- isosceles triangle
- obtuse triangle
- right triangle
- side
- triangle angle sum
- Triangle Inequality Theorem

**Special materials needed:**