Question

help please

Answer 1

what exactly?

Answer 2

Do you know 30-60-90 triangle rule?

Answer 3

no

Answer 4

best way is to use law of cosines

Answer 5

c^2 = a^2 + b^2 - 2ab cos C

Answer 6

plug in 60 for cos(c) (so basically cos(60)) and plug in 3 and 4 for a and b respectively

Answer 7

\[c^2=1^2+4^2-2\times 3 \times 4 \times \cos (60)\]

Answer 8

so replace that 1^2 with 3^2