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Answers:</h3>
Variation Constant: k = 7/6
y = 245/6 when x = 7 and z = 5
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Explanation:
"y varies jointly as x and z" means that y = kxz
We have (x,y,z) = (4,14,3) as one triple, so,
y = kxz
14 = k*4*3
14 = 12k
12k = 14
k = 14/12
k = 7/6 is the variation constant
The equation goes from y = kxz to y = (7/6)xz
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Plug in x = 7 and z = 5 to find y
y = (7/6)xz
y = (7/6)*7*5
y = (7/6)*(7/1)*(5/1)
y = (7*7*5)/(6*1*1)
y = 245/6
Step-by-step explanation:
hope it helps
<h3>stay safe healthy and happy.</h3>
Given:
cos 120°
To find:
The exact value of cos 120° in simplest form with a rational denominator.
Solution:
We have,
It can be written as
![[\because \cos (90^\circ-\theta)=-\sin \theta]](https://tex.z-dn.net/?f=%5B%5Cbecause%20%5Ccos%20%2890%5E%5Ccirc-%5Ctheta%29%3D-%5Csin%20%5Ctheta%5D)
![[\because \sin 30^\circ=\dfrac{1}{2}]](https://tex.z-dn.net/?f=%5B%5Cbecause%20%5Csin%2030%5E%5Ccirc%3D%5Cdfrac%7B1%7D%7B2%7D%5D)
Therefore, the exact value of cos 120° is 
.
Okay so basically domain =input and range =output. you can never have a negative number underneath the square root sign because it will make the answer imaginary (i), unless you are on that concept. Therefore the range is any number greater than 0. -> all real numbers greater than or = 0
for the range if you input 0 as x you will get -5, so any number you input after 0 will be greater than -5. so range is all real numbers greater than or equal to -5.
Sorry I forgot about that
