Question

In the figure, if m∠ABD = 120º, then m∠ADC =

picture: https://cdn.ple.platoweb.com/EdAssets/c892ccfd6d27437882833e5133611bbc?ts=635369975808230000
will fan helpers

Answer 1

First find angle BDA using the sine rule.
<ADC = 180 - <BDA

Answer 2

whats the sine rule?

Answer 3

Sine Rule:
a / sin A = b /sin B = c / sin C

Answer 4

how would i work this out like what number would i put where?

Answer 5

Chech triangle BAD in the diagram you are given values of 2 sides and 1 angle. Plug these into sine rule to get value of < BDA

Answer 6

note that side a is opposite angle A , b opposite <B and c is opposite <C.

Answer 7

ok that makes sense

Answer 8

ill try it

Answer 9

i cant get it srry

Answer 10

I'll give you one part of it
35 / sin 120 = ?

Answer 11

you need sin <BDA - what is the measure of the side opposite to this angle?

Answer 12

30/sin ?

Answer 13

30 / sin <BDA yes

so we have
35 / sin 120 = 30 / sin <BDA

solve for sin BDA

Answer 14

do you cross multiply

Answer 15

yes

Answer 16

i got 1.0 but its wrong

Answer 17

35 sin <BDA = 30 sin 120
divide both sides by 35

sin < BDA = (30 sin 120) / 35

Answer 18

909.3 or .7 im getting weird numbers and i typed it how it was written

Answer 19

just enter 30 * sin 120 - what do you get for that?

Answer 20

25.9?

Answer 21

25.98 yes
now divide that by 35 and you have the value of sin <BDA

Answer 22

1.34

Answer 23

i think you may have divided the wrong way
its 25.98 / 35

Answer 24

.74

Answer 25

the answer must be less than 1

when you have done that use the sin-1 key on your calculator to find the value of the <BDA

Answer 26

47.9

Answer 27

yes now find <BDA as above and subtract that from 180 to get <ADC ( beacuse adjacent angles add up to 180 degrees)

Answer 28

47.9 is correct

Answer 29

is that the final answer?

Answer 30

NO - check my previous post

Answer 31

132.1

Answer 32

looks good

Answer 33

thank you so much big help

Answer 34

yw