1. 6.1: Classifying Quadrilaterals
Geometry

2. Quadrilaterals
a polygon with 4 sides

3. Special Quadrilaterals
Parallelogram: A quadrilateral with both pairs of opposite sides parallel.
Rhombus: A parallelogram with four congruent sides.
Rectangle: A parallelogram with four right angles.
Square: A parallelogram with four right angles and four congruent sides.

4. Special Quadrilaterals
Kite: A quadrilateral with two pairs of adjacent sides congruent and no opposite sides congruent.
Trapezoid: A quadrilateral with exactly one pair of parallel sides.
The Isosceles Trapezoid is a trapezoid whose nonparallel opposite sides are congruent.

5. Classifying Quadrilaterals

6. Example 2:

7. Slope and Distance
Slope Formula:
Distance Formula:

8. Example 3: Step 1: Find the slope of each side.
Step 2: Use the distance formula to see if any pairs of sides are congruent.

9. Example 4:
Determine the most precise name for quadrilateral ABCD with vertices A(-3,3), B(2,4), C(3,-1), and D(-2, -2).

10. Example 5:

11. Example 6:
In parallelogram RSTU, 𝑚∠𝑅=2𝑥−10 𝑎𝑛𝑑 𝑚∠𝑆=3𝑥+50. 𝐹𝑖𝑛𝑑 𝑥.