Classifying Quadrilaterals — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. A Grade 4 square has 4 lines of symmetry.
A square has 4 lines of symmetry: the two diagonals and the two lines through opposite midpoints.
2. A non-square rectangle has 2 lines of symmetry.
A rectangle has 2 lines of symmetry through the midpoints of opposite sides; the diagonals are not lines of symmetry.
3. A non-square rhombus has 2 lines of symmetry.
A rhombus has 2 lines of symmetry along its diagonals because the diagonals bisect each other at right angles.
4. An isosceles trapezoid has 1 line of symmetry.
An isosceles trapezoid has 1 line of symmetry through the midpoints of its two parallel bases.
5. A scalene parallelogram has 0 lines of symmetry.
A parallelogram with unequal adjacent sides and no right angles has 0 lines of symmetry.
6. A general (scalene) trapezoid has 0 lines of symmetry.
If a trapezoid is not isosceles, no fold makes the halves match, so it has 0 lines of symmetry.
7. A kite (not a rhombus) has 1 line of symmetry.
A non-rhombus kite has 1 line of symmetry along the diagonal joining its two vertex angles where pairs of congruent sides meet.
8. Every quadrilateral has exactly 4 vertices, no matter the symmetry count.
All quadrilaterals have 4 vertices; symmetry counts vary but vertex count does not.
9. Among square, rectangle, rhombus, the shape with the most lines of symmetry is the square.
A square has 4 lines of symmetry, more than the 2 of a rectangle or rhombus.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
Square (Grade 4)
→ 4 lines of symmetry
1 line of symmetry
Non-square rectangle
→ 2 lines of symmetry
2 lines of symmetry
Non-square rhombus
→ 2 lines along the diagonals
2 lines along the diagonals
Isosceles trapezoid
→ 1 line of symmetry
4 lines of symmetry
Grade 4 students sort quadrilaterals by symmetry: square=4, rectangle=2 through midpoints, rhombus=2 along diagonals, isosceles trapezoid=1.