The multiplicative inverse of a number is the number when you multiply it, it gives you the product of 1.
So for - 27, what number will give us 1 when we multiply it by -27
-27 * -1/27 = 1
So the multiplicative inverse of -27 = -1/27
7/9 * 9/7 = 1
-9/16 * -16/9 = 1
So in essence, just take the number and flip it
-27 = -1 / 27
7/9 = 9/7
-9/16 = -16/9
Answer:
Below
Step-by-step explanation:
The length of this triangle is 3x+1 and the width is x.
The perimeter P is:
P= 2(3x+1)+2*x
P= 6x+2+2x
P= 8x+2
Let's evaluate it when x=1/2
●1/2 =0.5
P= 8*0.5+2 =4+2= 6 ft
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The area A is:
A = (3x+1)*x
A= 3x^2 +x
Let's evaluate it when x=0.5 feet
A= 3*0.5^2 +0.5
A= 3*0.25+0.5
A= 0.75 +0.5
A= 1.25 ft^2
So if boys is 6 and girls is 15 it would be 6/15, but that can be simplified to 2/5.
well, if the diameter is 5, thus its radius must be half that, or 2.5, and therefore, the radius of the one four times as much will be (4)(2.5).
Let's simply get their difference, since that'd be how much more is needed from the smaller to larger sphere.
![~\hfill \stackrel{\textit{surface area of a sphere}}{SA=4\pi r^2}\qquad \qquad r=radius~\hfill \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{\large difference of their areas}}{\stackrel{\textit{radius of (4)(2.5)}}{4\pi (4)(2.5)^2}~~ - ~~\stackrel{\textit{radius of 2.5}}{4\pi (2.5)^2}}\implies 100\pi -25\pi \implies 75\pi ~~ \approx ~~235.62~ft^2](https://tex.z-dn.net/?f=~%5Chfill%20%5Cstackrel%7B%5Ctextit%7Bsurface%20area%20of%20a%20sphere%7D%7D%7BSA%3D4%5Cpi%20r%5E2%7D%5Cqquad%20%5Cqquad%20r%3Dradius~%5Chfill%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7B%5Clarge%20difference%20of%20their%20areas%7D%7D%7B%5Cstackrel%7B%5Ctextit%7Bradius%20of%20%284%29%282.5%29%7D%7D%7B4%5Cpi%20%284%29%282.5%29%5E2%7D~~%20-%20~~%5Cstackrel%7B%5Ctextit%7Bradius%20of%202.5%7D%7D%7B4%5Cpi%20%282.5%29%5E2%7D%7D%5Cimplies%20100%5Cpi%20-25%5Cpi%20%5Cimplies%2075%5Cpi%20~~%20%5Capprox%20~~235.62~ft%5E2)