Answer:
B=34.2
C=105.8
c=12.0
Step-by-step explanation:
find B using the sine rule
(sin40÷8)=(sinB÷7)
rearrange
sin B= (sin40x7)÷8
sin B=0.562
make sure to use your calculator
then press shift sin to find B
B= 34.2°
to the nearest tenth means to 1 decimal place
sum of angles in a triangle is 180
so 180-(40+34.2)=105.8°=C
use sine rule again to find c
(sin105.8÷c)=(sin40÷8)
rearrange
c= (sin 105.8x8)÷sin40
c=12.0
