Question

Which trig function would I use to solve this?

Answer 1

sin(fi)=opposite/hypotenuse
cos(fi)=adjacent/hypotenuse
tan(fi)=opposite/adjacent

To know which one is opposite and which one adjacent you look from the corner where your fi is located, in your case fi=70 degrees. And you know hypotenuse is 14. Which formula has both x and hypotenuse?

Answer 2

To be more clear:

sin(fi)= (opposite side of fi)/hypotenuse
cos(fi)= (adjacent side to fi)/hypotenuse

Answer 3

You already know that hypotenuse=14 and you can calculate sin(70) or cos(70) . You just need to put that two in the correct formula that also includes x.

Answer 4

so i can use sin or cos?? because i thought i was supposed to use cos but i got the wrong answer when using cos70=adj/hyp=x/14

Answer 5

x doesn't touch 70 deg
so x is definitely not adjacent side to angle with deg 70

Answer 6

you could have used that other angle if you wanted to use cos
90-70=20
so cos(20)=x/14 would have been correct
or sin(70)=x/14 would have been correct

Answer 7

oh wow this was an hour ago :p

Answer 8

Nah it's cool because I'm still stuck lmao

Answer 9

but i'll try that now. thanks. :)