To find the length of SR, we can apply the cosine rule in triangle TSR:
SR2=TS2+TR2−2imesTSimesTRimesextcos(67°)
Substituting the given values:
SR2=(22)2+(18)2−2(22)(18)extcos(67°)
Calculating this:
SR2=484+324−2imes22imes18imes0.39073
SR2=497.5489
Thus,
SR=extsqrt(497.5489)≈22.33extm