Answer:
Step-by-step explanation:
Triangle RST is a right angle triangle.
From the given right angle triangle
RT represents the hypotenuse of the right angle triangle.
With 26 degrees as the reference angle,
ST represents the adjacent side of the right angle triangle.
RS represents the opposite side of the right angle triangle.
1) To determine RS, we would apply trigonometric ratio
Sin θ = opposite side/hypotenuse Therefore,
Sin 26 = RS/9.1
RS = 9.1Sin26 = 9.1 × 0.4384
RS = 4.0
2) To determine ST, we would apply trigonometric ratio
Cos θ = adjacent side/hypotenuse Therefore,
Cos 26 = ST/9.1
ST = 9.1Cos26 = 9.1 × 0.8988
ST = 8.1
3) The sum of the angles in a triangle is 180 degrees. Therefore,
∠R + 26 + 90 = 180
∠R = 180 - (26 + 90)
∠R = 64 degrees