It would be D, because to be a function, a set of ordered pairs cannot have the same x value. The y value can be the same though.
(5,6), (8,6), (9,6)
As you can see, all of the x values are different, so it is a function.
It's B - 1/√3
because tan is opposite side over adjacent
Answer:
Step-by-step explanation:
We know:
We have
Use 
![\left(\dfrac{1}{2}\right)^2+\cos^2\theta=1\\\\\dfrac{1}{4}+\cos^2\theta=1\qquad\text{subtract}\ \dfrac{1}{4}\ \text{from both sides}\\\\\cos^2\theta=\dfrac{4}{4}-\dfrac{1}{4}\\\\\cos^2\theta=\dfrac{3}{4}\to\cos\theta=\pm\sqrt{\dfrac{3}{4}}\to\cos\theta=\pm\dfrac{\sqrt3}{\sqrt4}\to\cos\theta=\pm\dfrac{\sqrt3}{2}\\\\\theta\in[0^o,\ 90^o],\ \text{therefore all functions have positive values or equal 0.}\\\\\cos\theta=\dfrac{\sqrt3}{2}](https://tex.z-dn.net/?f=%5Cleft%28%5Cdfrac%7B1%7D%7B2%7D%5Cright%29%5E2%2B%5Ccos%5E2%5Ctheta%3D1%5C%5C%5C%5C%5Cdfrac%7B1%7D%7B4%7D%2B%5Ccos%5E2%5Ctheta%3D1%5Cqquad%5Ctext%7Bsubtract%7D%5C%20%5Cdfrac%7B1%7D%7B4%7D%5C%20%5Ctext%7Bfrom%20both%20sides%7D%5C%5C%5C%5C%5Ccos%5E2%5Ctheta%3D%5Cdfrac%7B4%7D%7B4%7D-%5Cdfrac%7B1%7D%7B4%7D%5C%5C%5C%5C%5Ccos%5E2%5Ctheta%3D%5Cdfrac%7B3%7D%7B4%7D%5Cto%5Ccos%5Ctheta%3D%5Cpm%5Csqrt%7B%5Cdfrac%7B3%7D%7B4%7D%7D%5Cto%5Ccos%5Ctheta%3D%5Cpm%5Cdfrac%7B%5Csqrt3%7D%7B%5Csqrt4%7D%5Cto%5Ccos%5Ctheta%3D%5Cpm%5Cdfrac%7B%5Csqrt3%7D%7B2%7D%5C%5C%5C%5C%5Ctheta%5Cin%5B0%5Eo%2C%5C%2090%5Eo%5D%2C%5C%20%5Ctext%7Btherefore%20all%20functions%20have%20positive%20values%20or%20equal%200.%7D%5C%5C%5C%5C%5Ccos%5Ctheta%3D%5Cdfrac%7B%5Csqrt3%7D%7B2%7D)
Answer:
x= -1/24
Step-by-step explanation:
-5/6x = 20
-5 = 6x × 20
-5 = 120x
-5/120 = x
-1/24 = x
The answer would be 0.055
