We are looking for a new number which is 30 less than 10. We will get the new number by subtracting 30 from 10. We write it down as: 10-30=-20
And finally the solution for: What number is 30 less than 10? is -20
Hope this helps!!
Answer:
(a) ![l = -w + 21](https://tex.z-dn.net/?f=l%20%3D%20-w%20%2B%2021)
(b) Domain:
<em>(See attachment for graph)</em>
(c) ![f(w) = -w + 21](https://tex.z-dn.net/?f=f%28w%29%20%3D%20-w%20%2B%2021)
Step-by-step explanation:
Given
![2(l + w) = 42](https://tex.z-dn.net/?f=2%28l%20%2B%20w%29%20%3D%2042)
![l = length](https://tex.z-dn.net/?f=l%20%3D%20length)
![w = width](https://tex.z-dn.net/?f=w%20%3D%20width)
Solving (a): A function; l in terms of w
All we need to do is make l the subject in ![2(l + w) = 42](https://tex.z-dn.net/?f=2%28l%20%2B%20w%29%20%3D%2042)
Divide through by 2
![l + w = 21](https://tex.z-dn.net/?f=l%20%2B%20w%20%3D%2021)
Subtract w from both sides
![l + w - w = 21 - w](https://tex.z-dn.net/?f=l%20%2B%20w%20-%20w%20%3D%2021%20-%20w)
![l = 21 - w](https://tex.z-dn.net/?f=l%20%20%3D%2021%20-%20w)
Reorder
![l = -w + 21](https://tex.z-dn.net/?f=l%20%3D%20-w%20%2B%2021)
Solving (b): The graph
In (a), we have:
![l = -w + 21](https://tex.z-dn.net/?f=l%20%3D%20-w%20%2B%2021)
Since l and w are the dimensions of the fence, they can't be less than 1
So, the domain of the function can be ![0](https://tex.z-dn.net/?f=0%20%3Cw%20%3C%2021)
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To check this
When ![w = 1](https://tex.z-dn.net/?f=w%20%3D%201)
![l = -1 + 21](https://tex.z-dn.net/?f=l%20%3D%20-1%20%2B%2021)
![l = 20](https://tex.z-dn.net/?f=l%20%3D%2020)
![(w,l) = (1,20)](https://tex.z-dn.net/?f=%28w%2Cl%29%20%3D%20%281%2C20%29)
When ![w = 20](https://tex.z-dn.net/?f=w%20%3D%2020)
![l = -20 + 21](https://tex.z-dn.net/?f=l%20%3D%20-20%20%2B%2021)
![l = 1](https://tex.z-dn.net/?f=l%20%3D%201)
--------------------------------------------------------------------------------------------------
<em>See attachment for graph</em>
<em></em>
Solving (c): Write l as a function ![f(w)](https://tex.z-dn.net/?f=f%28w%29)
In (a), we have:
![l = -w + 21](https://tex.z-dn.net/?f=l%20%3D%20-w%20%2B%2021)
Writing l as a function, we have:
![l = f(w)](https://tex.z-dn.net/?f=l%20%3D%20f%28w%29)
Substitute
for l in ![l = -w + 21](https://tex.z-dn.net/?f=l%20%3D%20-w%20%2B%2021)
becomes
![f(w) = -w + 21](https://tex.z-dn.net/?f=f%28w%29%20%3D%20-w%20%2B%2021)
Answer:
Step-by-step explanation:
i'll do a few of them
1) one inch plus a half inch plus an eighth inch plus a sixteenth inch
1 + 1/2 + 1/8 + 1/16 read the tick marks
1 + 8/16 + 2/16 + 1/16 find a common denominators
1 and 11/16 add the sixteenth numerator
2)
3)
4) 6 inch plus an eighth inch plus a sixteenth inch
6 + 1/8 + 1/16 read the tick marks
6 + 2/16 + 1/16 find a common denominators
6 and 3/16 add the sixteenth numerator
5) nine inch plus a quarter inch plus an eighth inch
9 + 1/4 + 1/8 read the tick marks
9 + 2/8 + 1/8 find a common denominators
9 and 3/8 add the sixteenth numerator