Answer:
Karen is 71 years old
Step-by-step explanation:
Known
Karen=Jack +35
Frank=1/2 Jack
Jenifer=Frank+17
If Jenifer=35
35=Frank+17
18 = Frank
18=1/2 Jack
36= Jack
Karen= Jack+35=36+35=71
Is there a picture to go along with it? Because it's asking for the measure of ABD which is a triangle or a ray or something
If you go on jiskha because you will find your answer by looking through search bar but the answe is B
Given:
![\cos \theta =\dfrac{3}{5}](https://tex.z-dn.net/?f=%5Ccos%20%5Ctheta%20%3D%5Cdfrac%7B3%7D%7B5%7D)
![\sin \theta](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%20%3C0)
To find:
The quadrant of the terminal side of
and find the value of
.
Solution:
We know that,
In Quadrant I, all trigonometric ratios are positive.
In Quadrant II: Only sin and cosec are positive.
In Quadrant III: Only tan and cot are positive.
In Quadrant IV: Only cos and sec are positive.
It is given that,
![\cos \theta =\dfrac{3}{5}](https://tex.z-dn.net/?f=%5Ccos%20%5Ctheta%20%3D%5Cdfrac%7B3%7D%7B5%7D)
![\sin \theta](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%20%3C0)
Here cos is positive and sine is negative. So,
must be lies in Quadrant IV.
We know that,
![\sin^2\theta +\cos^2\theta =1](https://tex.z-dn.net/?f=%5Csin%5E2%5Ctheta%20%2B%5Ccos%5E2%5Ctheta%20%3D1)
![\sin^2\theta=1-\cos^2\theta](https://tex.z-dn.net/?f=%5Csin%5E2%5Ctheta%3D1-%5Ccos%5E2%5Ctheta)
![\sin \theta=\pm \sqrt{1-\cos^2\theta}](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%3D%5Cpm%20%5Csqrt%7B1-%5Ccos%5E2%5Ctheta%7D)
It is only negative because
lies in Quadrant IV. So,
![\sin \theta=-\sqrt{1-\cos^2\theta}](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%3D-%5Csqrt%7B1-%5Ccos%5E2%5Ctheta%7D)
After substituting
, we get
![\sin \theta=-\sqrt{1-(\dfrac{3}{5})^2}](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%3D-%5Csqrt%7B1-%28%5Cdfrac%7B3%7D%7B5%7D%29%5E2%7D)
![\sin \theta=-\sqrt{1-\dfrac{9}{25}}](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%3D-%5Csqrt%7B1-%5Cdfrac%7B9%7D%7B25%7D%7D)
![\sin \theta=-\sqrt{\dfrac{25-9}{25}}](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%3D-%5Csqrt%7B%5Cdfrac%7B25-9%7D%7B25%7D%7D)
![\sin \theta=-\sqrt{\dfrac{16}{25}}](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%3D-%5Csqrt%7B%5Cdfrac%7B16%7D%7B25%7D%7D)
![\sin \theta=-\dfrac{4}{5}](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%3D-%5Cdfrac%7B4%7D%7B5%7D)
Therefore, the correct option is B.