Answer:
Step-by-step explanation:
Since we know the two sides and one angle, we would apply the law of Cosines which is expressed as
a² = b² + c² - 2abCosA
Where a,b and c are the length of each side of the triangle and A is the angle corresponding to a. Likening the expression to the given triangle, it becomes
QR² = RS² + QS² - 2(RS × QS)CosS
QR² = 40² + 35² - 2(40 × 35)Cos34
QR² = 1600 + 1225 - 2(1400)Cos34
QR² = 2825 - 2321.2
QR² = 503.8
QR = √503.8
QR = 22.4
