Shapes belong to families. All squares are rectangles, because they have four right angles. All rectangles are parallelograms, because they have two pairs of parallel sides. All parallelograms are quadrilaterals.
But not every rectangle is a square, because its sides may not all be equal. A rhombus is a parallelogram with four equal sides. A square is the only shape that is both a rectangle and a rhombus. Use the properties, not the look, to decide.
Worked example
Which shape has four equal sides and four right angles?
- Four right angles: a rectangle or a square.
- Four equal sides as well: a square.
Answer:a square
Key words
- property
- a fact about a shape
- parallelogram
- two pairs of parallel sides
- hierarchy
- families inside bigger families
Practise this
New questions every time.
Common Core-referenced: 5.G.B.3