**Title:** Construct This!

**Description:**
Students will construct equilateral triangles, squares, and regular hexagons inscribed in circles using the free GeoGebra computer program.
**Standard(s): **

[MA2015] GEO (9-12) 13: Construct an equilateral triangle, a square, and a regular hexagon inscribed in a circle. [G-CO13]

**Subject:**Mathematics (9 - 12)

**Title:**Construct This!

**Description:**Students will construct equilateral triangles, squares, and regular hexagons inscribed in circles using the free GeoGebra computer program.

**Title:** All in the Family

**Description:**
In this Illuminations lesson, students use a dynamic geometry applet to conjecture about the relationships between characteristics of a square: side length, diagonal length, perimeter, and area. Students use graphs to represent functional relationships between two characteristics, such as diagonal length as a function of perimeter. In addition, there are links to online activities, reproducibles, and other related resources.
**Standard(s): **

[MA2015] GEO (9-12) 13: Construct an equilateral triangle, a square, and a regular hexagon inscribed in a circle. [G-CO13]

**Subject:**Mathematics

**Title:**All in the Family

**Description:**In this Illuminations lesson, students use a dynamic geometry applet to conjecture about the relationships between characteristics of a square: side length, diagonal length, perimeter, and area. Students use graphs to represent functional relationships between two characteristics, such as diagonal length as a function of perimeter. In addition, there are links to online activities, reproducibles, and other related resources.

**Thinkfinity Partner:**Illuminations

**Grade Span:**9,10,11,12

**Title:** IGD: Simson Line

**Description:**
This student interactive, from Illuminations, helps students understand and investigate a triangle s Simson line, which is the line passing through the feet of the perpendiculars dropped from P to the three sides of a triangle. Students construct the Simson line for a given triangle using the interactive applet.
**Standard(s): **

[MA2015] MI1 (9-12) 11: Describe the development of mathematical tools and their applications. (Alabama)

**Subject:**Mathematics

**Title:**IGD: Simson Line

**Description:**This student interactive, from Illuminations, helps students understand and investigate a triangle s Simson line, which is the line passing through the feet of the perpendiculars dropped from P to the three sides of a triangle. Students construct the Simson line for a given triangle using the interactive applet.

**Thinkfinity Partner:**Illuminations

**Grade Span:**9,10,11,12

**Title:** Triangle Classification

**Description:**
This student interactive, from an Illuminations lesson, allows students to turn a segment into a right triangle, an isosceles triangle, and an obtuse triangle.
**Standard(s): **

[MA2015] GEO (9-12) 17: Prove theorems about triangles. *Theorems include a line parallel to one side of a triangle divides the other two proportionally, and conversely; and the Pythagorean Theorem proved using triangle similarity.* [G-SRT4]

**Subject:**Mathematics

**Title:**Triangle Classification

**Description:**This student interactive, from an Illuminations lesson, allows students to turn a segment into a right triangle, an isosceles triangle, and an obtuse triangle.

**Thinkfinity Partner:**Illuminations

**Grade Span:**9,10,11,12