Given:
In a set of 3 numbers the first is a positive integer, the second is 3 more than the first and the 3rd is a square of the second.
To find:
The equation for the given situation if the sum of the numbers is 77.
Solution:
a. Let the first number in the set is x.
The second is 3 more than the first. So, the second number is 
.
The 3rd number is a square of the second. So, the third number is 
.
Therefore, the first, second and third numbers are 
respectively.
b. The sum of the numbers is 77.
First number + Second number + Third number = 77
c. So, the equation in terms of x is:
Therefore, the required equation is .
d. On simplification, we get
![[\because (a+b)^2=a^2+2ab+b^2]](https://tex.z-dn.net/?f=%5B%5Cbecause%20%28a%2Bb%29%5E2%3Da%5E2%2B2ab%2Bb%5E2%5D)
Subtract 77 from both sides.
Therefore, the simplified form of the required equation is .
Step-by-step explanation:
a) 24.7×52.3=1291.81
On rounding off to 3 significant digits we get
1290
b)
=31.304951
On rounding off to 5 significant figures we get
=31.305
c)
![\sqrt[3]{78} = 4.27265](https://tex.z-dn.net/?f=%20%5Csqrt%5B3%5D%7B78%7D%20%20%3D%204.27265)
On rounding off to 2 significant figures we get
=4.3
Hence required answers
a)1290
b)31.305
c)4.3
I hope it helped you
Answer:
17.5
Step-by-step explanation:
180 = 40+ 8x
140 = 8x
17.5 = x
<span>for that, what you need is a calculator... like say a TI(texas instruments) 83 or 83plus or higher, will do regressions, if you have an android device like a phone or tablet, you can also get an app from the play store "Andie's graph", is a TI calculator emulator, it works just like the calculator itself, you'd only need the ROM
</span><span>that said, you can also use some online calculators for that.
</span>
<span>I could give you a direct link to one, but this site has issues with links, if you do a quick search in google for "keisan exponential regression calculator", it should be the first link, is from the Casio site.
</span>
<span>you could do regressions in a spreadsheet as well.... you could check online for an "addin" or "extension", if you use MS Excel, pretty sure there are some addins for regressions.
</span>
if I recall correctly, Excel does regressions natively, but the addins are just frontends, is all, just some added interfacing.
anyhow, if you have an Android device Andie Graph works peachy, I have an 83plus, 84, 86 in it, they all work just like my old TI83plus.
there's also an app in the play store called Graph89, is an emulator for a TI89, the same you need a tiny little file, and texas instruments provides them, have also, works peachy too.
