Welcome, student-learner! Quadrilaterals are four-sided polygons with four angles (Math.com, 2005a). In this activity, you will deal with the learning competencies of identifying and describing the different kinds of quadrilaterals: square, rectangle, parallelogram, and rhombus; determining the conditions that make a quadrilateral a parallelogram; and proving theorems on the different kinds of parallelogram (rectangle, rhombus, square)(Department of Education, 2016). Such competencies are appropriate for 4th and 9th graders (Department of Education, 2016). You will be playing with quadrilaterals and changing their measurements. Be sure to follow the instructions in every section and answer the questions that follow honestly. The applets in this activity are inspired by the works of Kim, Rosalie83, & McCarthy (n.d.).

Explore the parallelogram below.

Explore the rectangle below.

Explore the rhombus below.

Explore the square below.