Calculate angles

1 Twoangles,aandb,areadjacent

onastraightline.

a) Measureanglesaandb.

a= b=

b) Whatisthetotalofthetwoangles?

c) Completethesentence.

Adjacentanglesonastraightline

2 a) Completethefactfamilyforthebarmodel.

180

a 63

a+63= 180– =a

63+ = 180–a=

b) Tickthecalculationinparta)thathelpsyouworkoutthe

valueofa.

c) Workoutthevalueofa. a=

d) Howdoesthebarmodelhelpyoutocalculateanglea?

3 Workouttheunknownangles.

a) d)

e= a=

b) e)

g= y=

c) f)

x= z =

4 Doraisfacinginthedirectionshownbythearrow.

Shedoesafullturnclockwise.

a) ShowDora’sturnonthediagram.

b) Howmanydegreesdid

Doraturnthrough?

c) Useyouranswertopartb)tohelpyoucompletethesentence.

Anglesaroundapoint©WhiteRoseMaths2020

Dora

ab

e

gy

a

x z

58°

141°62°

132°

49°

43°37°

a63°

5 Workouttheunknownangles.

a) c)

c= a=

b) d)

x= z=

6

DoyouagreewithTommy?

Explainyouranswer.

©WhiteRoseMaths2020

7 Usetheinformationtoworkouttheunknownangles.

a) Angleaishalfthesizeof

angleb.

b) Angleaisfourtimesthesize

ofangleb.

a= a=

b= b=

8 Thepiechartshowssomechildren’sfavouritesnacks.

Aquarterofthechildrensaidchocolatewastheirfavouritesnack.

Fivetimesasmanychildrenvotedforfruitasvotedforsweets.

Workoutthesizeoftheangleforeachsectorinthepiechart.

chocolate sweets fruit

c

xz

a

100°

110°

101°

64°20°

118°62°

62°

Angle b is 116° because angles on a straight line add

up to 180°.

b64°

ab

ab

fruit

chocolate

sweets