The line with equation a + 4b = 0 coincides with the terminal side of an angle θ in standard position and cos θ > 0. What is the value of sinθ ?
a. -(√17/17)
b. -(17/√17)
c. -(14/√17)
d. -(17/√14)

Respuesta :

Answer:

Option A. -([tex]\frac{\sqrt{17}}{17}[/tex])

Step-by-step explanation:

Equation of a given line is a + 4b = 0 or b = -[tex]\frac{1}{4}a[/tex]

This in the form of y = mx + b, which is slope-intercept form.

Here slope of the line is ([tex]-\frac{1}{4}[/tex]).

Or tanθ = [tex]\frac{(-1)}{4}[/tex]

This line coincides with the terminal side of the angle in standard position where cosθ > 0

Since tanθ = [tex]\frac{\text{Height}}{\text{Base}}[/tex]

and sinθ = [tex]\frac{\text{height}}{\txt{Hypotenuse}}[/tex]

Hypotenuse = [tex]\sqrt{\text{height}^{2}+\text{Base}^{2}}[/tex]

                     = [tex]\sqrt{(1^{2}+4^{2})}[/tex]

                     = [tex]\sqrt{17}[/tex]

Since tanθ is negative and cosθ > 0 that means θ lie in fourth quadrant.

Therefore, sinθ will be negative.

[ [tex]\frac{-sin\theta}{+cos\theta}=-tan\theta[/tex] ]

sinθ = -[tex]\frac{1}{\sqrt{17}}[/tex]

       = -[tex]\frac{1}{\sqrt{17}}\times \frac{\sqrt{17} }{\sqrt{17}} = -\frac{\sqrt{17}}{17}[/tex]

Answer will be option A.

Answer: A

Step-by-step explanation: I took the test