Respuesta :

Answer:

∠A ≈ 19.47°

Step-by-step explanation:

As you know , the angle that tangent makes with the radius at the point of tangency is 90°.

∴∠OKA = 90°

As  AO = 15 and OK = 5 ,

[tex]sin(A) = \frac{OK}{AO}[/tex]

[tex]sin(A) = \frac{5}{15} [/tex]

[tex]sin(A) = \frac{1}{3} [/tex]

∠A = [tex]sin^{-1} (\frac{1}{3} )[/tex]

∠A ≈ 19.47°

Answer:

[tex]\mathbf{m\angle A = sin^{-1}(\frac{1}{3}) \approx 19.47^{\circ}}[/tex]

Step-by-step explanation:

This question involves some basic knowledge of trigonometric function. The following formula only works for right angled triangles.

[tex]\mathbf{sin(x) = \frac{perpendicular}{hypotenuse}}[/tex]

In ΔAKO,

m∠AKO = 90°

Therefore ΔAKO is a right angled triangle. If we take ∠A into consideration then base will be AK, perpendicular will be OK and hypotenuse will be AO.

AO = 15

OK = 5

[tex]\therefore \mathrm{sin(\angle A) = \frac{OK}{AO} = \frac{5}{15} = \frac{1}{3}}[/tex]

[tex]\mathrm{sin(\angle A)=\frac{1}{3}}[/tex]

[tex]\mathrm{\angle A=sin^{-1}(\frac{1}{3})}[/tex]

To calculate [tex]\mathrm{sin^{-1}(\frac{1}{3})}[/tex] use scientific calculator

value of [tex]\mathrm{sin^{-1}(\frac{1}{3})}[/tex] is approximately equal to 19.47°

Therefore [tex]\mathbf{m\angle A \approx 19.47}[/tex]

(NOTE : When a line passing through center of a circle, is drawn to a tangent at the point of tangency then the angle made between then is 90°

Therefore m∠AKO = 90°)