Classifying Triangles and Quadrilaterals
Identify shapes by sides, angles, and parallel lines
Classifying Triangles and Quadrilaterals
Identify shapes by sides, angles, and parallel lines
Math - Grade 4-5
- 1
A triangle has side lengths of 5 cm, 5 cm, and 5 cm. Classify the triangle by its sides.
Look for how many sides have the same length.
The triangle is equilateral because all three side lengths are equal. - 2
A triangle has side lengths of 6 inches, 6 inches, and 3 inches. Classify the triangle by its sides.
The triangle is isosceles because exactly two sides have the same length. - 3
A triangle has side lengths of 4 cm, 5 cm, and 7 cm. Classify the triangle by its sides.
A scalene triangle has no equal sides.
The triangle is scalene because all three side lengths are different. - 4
A triangle has one angle that measures 90 degrees. Classify the triangle by its angles.
The triangle is a right triangle because it has one angle that measures exactly 90 degrees. - 5
A triangle has angle measures of 40 degrees, 60 degrees, and 80 degrees. Classify the triangle by its angles.
Acute angles are smaller than right angles.
The triangle is an acute triangle because all three angles are less than 90 degrees. - 6
A triangle has angle measures of 25 degrees, 35 degrees, and 120 degrees. Classify the triangle by its angles.
The triangle is an obtuse triangle because one angle is greater than 90 degrees. - 7
A quadrilateral has 4 sides, 4 right angles, and opposite sides that are equal in length. The adjacent sides are not all equal. What is the most specific name for this shape?
A square would need all four sides to be equal.
The most specific name for this shape is a rectangle because it has four right angles and opposite sides that are equal. - 8
A quadrilateral has 4 equal sides and 4 right angles. What is the most specific name for this shape?
The most specific name for this shape is a square because it has four equal sides and four right angles. - 9
A quadrilateral has exactly one pair of parallel sides. What type of quadrilateral is it?
Parallel sides stay the same distance apart and do not meet.
The quadrilateral is a trapezoid because it has exactly one pair of parallel sides. - 10
A quadrilateral has 4 equal sides. Its opposite angles are equal, but it does not have 4 right angles. What is the most specific name for this shape?
The most specific name for this shape is a rhombus because all four sides are equal and it does not have to have right angles. - 11
Decide whether the statement is true or false: Every square is a rectangle. Explain your answer.
Think about the properties a rectangle must have.
The statement is true because every square has four right angles and opposite sides that are equal, which are properties of a rectangle. - 12
Decide whether the statement is true or false: Every rectangle is a square. Explain your answer.
The statement is false because a rectangle does not need to have four equal sides, but a square does. - 13
A shape has 4 sides. Both pairs of opposite sides are parallel, and the shape has no right angles. What general type of quadrilateral is it?
Rectangles, squares, and rhombuses are special kinds of parallelograms, but this question asks for the general type.
The shape is a parallelogram because both pairs of opposite sides are parallel. - 14
Classify a triangle that has two equal sides and one angle that measures 90 degrees. Use both side and angle names.
Use one word for the side lengths and one word for the angle type.
The triangle is an isosceles right triangle because it has two equal sides and one right angle. - 15
Mia says a quadrilateral with 4 equal sides must always be a square. Is Mia correct? Explain your answer.
Mia is not correct because a rhombus has 4 equal sides but does not always have 4 right angles. A shape must have 4 equal sides and 4 right angles to be a square.