Page 875 - Algebra 1

Classify Quadrilaterals
Skills Bank Lesson 14
A quadrilateral is a two-dimensional figure with four sides and four angles. The table shows five special quadrilaterals and their properties.
Parallelogram
Opposite sides are parallel and congruent. Opposite angles are congruent.
Rectangle
Parallelogram with four right angles
Rhombus
Parallelogram with four congruent sides
Square
Rectangle with four congruent sides
Trapezoid
Quadrilateral with exactly two parallel sides May have two right angles
Example
1
Classifying Quadrilaterals
a. Identify which statement is always true.
• A trapezoid is also a parallelogram. • A square is also a rhombus.
• A parallelogram is also a rectangle. • A rectangle is also a square.
SOLUTION
A square is also a rhombus is true, because a square is a parallelogram with four congruent sides.
Skills Bank Practice
Complete each statement.
a. A square is also a .
c. All trapezoids are also .
d. A is any two-dimensional figure with four straight sides and four angles.
b. Identify which statement is not always true.
• A quadrilateral has 4 sides.
• A quadrilateral has 4 angles.
• A quadrilateral has straight sides. • A quadrilateral has right angles.
SOLUTION
A quadrilateral does not always have right angles.
b. A rhombus is sometimes a .
860 Saxon Algebra 1