Construct angle ABC in which AB=7cm,AC=9•5 and ABC=120°.measure BC.

1 answer

Ok, I did that, after assuming that you meant: AC = 9.5

Not going to measure, since we can find BC using basic trig
SinC/7 = sin120/9.5
sinC = 7sin120/9.5 = ...
angle C = appr 39.65°
which makes angle A = 20.35°

so repeat:
BC/sin20.35 = 9.5/sin120
BC = 9.5sin20.35/sin120
= ....

compare with your measurement