Use trig ratios to find the measure of the angle in this Triangle (Image)
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Answer:
θ = 36.9°
Step-by-step explanation:
Trigonometric ratios in a right triangle will be,
Sinθ = [tex]\frac{\text{Opposite side}}{\text{Hypotenuse}}[/tex] = [tex]\frac{\text{AC}}{\text{AB}}[/tex]
Cosθ = [tex]\frac{\text{Adjacent side}}{\text{Hypotenuse}}[/tex] = [tex]\frac{\text{BC}}{\text{AB}}[/tex]
Tanθ = [tex]\frac{\text{Opposite side}}{\text{Adjacent side}}[/tex] = [tex]\frac{\text{AC}}{\text{BC}}[/tex]
In the picture attached,
Given sides are,
AB = 5 and BC = 4
Therefore, to find the given angle θ only Cosine will be applicable.
Cos θ = [tex]\frac{\text{BC}}{\text{AB}}[/tex]
= [tex]\frac{4}{5}[/tex]
θ = [tex]Cos^{-1}(0.8)[/tex]
θ = 36.87°
θ ≈ 36.9°