Question

Please answer this question now

Answer 1

`r = 17.5`

Explanation:

Given ∆TRS,

Where,

m < R = 105°

TR = s = 15

RS = t = 6

ST = r = ?

Find r using the Law of Cosines.

`r^2 = s^2 + t^2 - 2*s*t*cos(R)`

Plug in the values stated above into the formula

`r^2 = 15^2 + 6^2 - 2*15*6*cos(105)`

`r^2 = 225 + 36 - 180*(-0.2588)`

`r^2 = 261 + 46.584`

`r^2 = 307.584`

`r = √(307.584)`

`r = 17.5` (to the nearest tenth)