Area - triangles, quadrilaterals, compound shapes

There are 53 NRICH Mathematical resources connected to Area - triangles, quadrilaterals, compound shapes
Areas and Ratios
problem
Favourite

Areas and ratios

Age
16 to 18
Challenge level
filled star filled star empty star
Do you have enough information to work out the area of the shaded quadrilateral?
Of all the areas
problem
Favourite

Of all the areas

Age
14 to 16
Challenge level
filled star filled star empty star
Can you find a general rule for finding the areas of equilateral triangles drawn on an isometric grid?
Isosceles Triangles
problem
Favourite

Isosceles triangles

Age
11 to 14
Challenge level
filled star empty star empty star
Draw some isosceles triangles with an area of $9$cm$^2$ and a vertex at (20,20). If all the vertices must have whole number coordinates, how many is it possible to draw?
Areas of parallelograms
problem
Favourite

Areas of parallelograms

Age
14 to 16
Challenge level
filled star filled star empty star
Can you find the area of a parallelogram defined by two vectors?
So Big
problem
Favourite

So big

Age
16 to 18
Challenge level
filled star filled star empty star
One side of a triangle is divided into segments of length a and b by the inscribed circle, with radius r. Prove that the area is: abr(a+b)/ab-r^2
Trapezium Four
problem
Favourite

Trapezium four

Age
14 to 16
Challenge level
filled star filled star empty star
The diagonals of a trapezium divide it into four parts. Can you create a trapezium where three of those parts are equal in area?
Twice as Big?
problem
Favourite

Twice as big?

Age
7 to 11
Challenge level
filled star empty star empty star

Investigate how the four L-shapes fit together to make an enlarged L-shape. You could explore this idea with other shapes too.

Gutter
problem
Favourite

Gutter

Age
14 to 16
Challenge level
filled star filled star empty star
Manufacturers need to minimise the amount of material used to make their product. What is the best cross-section for a gutter?
Pick's Theorem
problem
Favourite

Pick's theorem

Age
14 to 16
Challenge level
filled star filled star empty star
Polygons drawn on square dotty paper have dots on their perimeter (p) and often internal (i) ones as well. Find a relationship between p, i and the area of the polygons.
Doesn't add up
problem
Favourite

Doesn't add up

Age
14 to 16
Challenge level
filled star filled star empty star

In this problem we are faced with an apparently easy area problem, but it has gone horribly wrong! What happened?