Grade 4 · Math · Unit 13 of 16
Triangles, Quadrilaterals & Angles
Name shapes by their sides and angles, and find missing angles
What your child practises
Triangles are named by their sides (equilateral, isosceles, scalene) and by their angles (acute, right, obtuse). Quadrilaterals include squares, rectangles, rhombuses, parallelograms and trapezoids. Complementary angles add to 90° and supplementary angles add to 180°.
Alberta Curriculum learning outcome: 4G1.1 · classifying triangles and quadrilaterals, and complementary and supplementary angles
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Which quadrilateral always has 4 equal sides?
- trapezoid
- rhombus
- rectangle
- parallelogram
Show answer
rhombus
Hint: A rhombus has 4 equal sides. A rectangle or parallelogram can have long and short sides.
Question 2
A triangle has sides 5 cm, 5 cm and 5 cm. What kind of triangle is it, by its sides?
- isosceles
- equilateral
- scalene
Show answer
equilateral
Hint: Equilateral means all 3 sides are equal.
Question 3
Two sides of a shape are parallel and the other two are not. The shape has 4 sides. It is a…
- rectangle
- rhombus
- square
- trapezoid
Show answer
trapezoid
Hint: A trapezoid has only one pair of parallel sides.
Question 4
Which pair of angles is complementary?
- 65° and 35°
- 65° and 115°
- 65° and 25°
- 65° and 15°
Show answer
65° and 25°
Hint: Complementary angles add to 90°.
Question 5
Two angles are complementary. One angle is 55°. What is the other angle?
answer box°
Show answer
35 °
Hint: Complementary angles add to 90°.
Question 6
Two angles are complementary. One angle is 56°. What is the other angle?
answer box°
Show answer
34 °
Hint: Complementary angles add to 90°.