Question

Calculate the length b to two decimal places.

Answer 1

you need the law of cosines

\[b^2 = 12^2 + 15^2 - 2\times 12 \times 15 \times \cos(108)\]

don't foget to take the square root to get the correct answer

Answer 2

=144+225-360 cos (106)

Answer 3

@campbell_st ?

Answer 4

9 cos (106)

Answer 5

thats correct....

so get a number answer and then take the square root

the length is the longest side so should be longer than 15

Answer 6

b= 3cos(106), so what now do i use my calculator and times 9 by 106 and click cos right after?

Answer 7

@campbell_st

Answer 8

well when you put the initial values into the calculator you get

\[b^2 = 468.299\]

now take the square root

Answer 9

i got 21.64

Answer 10

same answer as I got. Well done

Answer 11

thank you
@campbell_st