The value of length ER rounded to the nearest tenth is 17.9 units (Option C)
Trigonometric ratios
The trigonometric ratios which has been proven as regarding right angle triangles are given below:
Sine θ = Opposite / Hypothenus
Cos θ = Adjacent / Hypothenus
Tan θ = Opposite / Adjacent
With above information in mind, we can easily determine the length of ER in the question. This is illustrated below:
How to determine the length of ER
From the question given above, which is summarized in the diagram (see attached photo) the following data were obtained:
- Hypothenus (MR) = 37 units
- Angle R = 61 °
- Adjacent (ER) = ?
Since we looking for the Adjacent (ER), the best trig ratio to use is the Cos θ ratio. This can be obtained as illustrated below:
Cos θ = Adjacent / Hypothenus
Cos 61 = ER / 37
Cross multiply
ER = 37 × Cos 61
ER = 37 × 0.4848
ER = 17.9 units
Thus, the length of ER to the nearest tenth is 17.9 units
Learn more about trigonometric ratios:
brainly.com/question/26719838
#SPJ1
