1 Completethesentencestodescribe

thetriangle.

Thetrianglehas fullsquares.

Thetrianglehas halfsquares.

Theareaofthetriangle

is cm2

2 Countsquarestoworkouttheareaofeachtriangle.

a) c)

b)

3 Countsquarestoestimatetheareaofeachtriangle.

a) c)

b)

Whyareyouranswersestimates?

4 a)Workouttheareasoftheshapesbycountingsquares.

b) Whatdoyounoticeaboutyouranswerstoparta)?

Explorethisusingotherrectangles.

c) Writeyourfindings.

Areaofa triangle (1)

©WhiteRoseMaths2019

1cm

1cm

1cm

1cm

1cm

1cm

1cm

1cm

d) 1cm

1cm

1cm

1cm

1cm

1cm

1cm

1cm

1cm

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1cm

1cm

5 Drawatrianglethathasanareaofapproximately15cm2

Compareanswerswithapartner.

6

DoyouagreewithEva’sestimate?

Talkaboutitwithapartner.

7 Drawtriangleswiththeseareas.

1cm22cm23cm24cm25cm26cm2

Talktoapartneraboutthebeststrategiesfordrawingthetriangles.

Areaofa triangle (1)

©WhiteRoseMaths2019

1cm

1cm

I estimate the size of the triangle to be about 16 cm2

3 Countsquarestoestimatetheareaofeachtriangle.

a) c)

b)

Whyareyouranswersestimates?

4 a)Workouttheareasoftheshapesbycountingsquares.

b) Whatdoyounoticeaboutyouranswerstoparta)?

Explorethisusingotherrectangles.

c) Writeyourfindings.

1cm

1cm

1cm

1cm

1cm

1cm

1cm

1cm

1cm

1cm