Shapes, triangles and area with tiles
Answers are for parents and teachers.
1
Name every category that a square belongs to.
Square, rectangle, rhombus, parallelogram, quadrilateral, polygon.
2
A triangle has sides 9 cm, 12 cm and 15 cm. Name it by its sides. (Its biggest angle is a right angle: name it by its angles too.)
Scalene (no equal sides) and right.
3
Draw a rectangle on squared paper whose area is 12 square centimetres. Give its length and width.
For example 6 cm by 2 cm, 4 cm by 3 cm or 12 cm by 1 cm (length × width = 12).
4
Find the area of a rectangle 2 1/2 m by 3/5 m.
5/2 × 3/5 = 15/10 = 3/2 = 1 1/2 square metres.
5
Mostafa says a triangle can have two right angles. Is he right? Think about the two sides that would have to meet.
No. If two angles were right angles, the two sides leaving them would both be at 90° to the base, so they would be parallel and would never meet to close the triangle.