Rearranging an equation to solve for a variable

Linear, quadratic, module, parametric equations

Rearranging an equation to solve for a variable

Postby Guest » Fri Jun 04, 2021 4:34 pm

In this problem, I need to rearrange the equation to solve for the variable of interest which is TSS.

I have been given the following values to use to solve the problem:

RSS = 246.68
R2 = 0.78
However, when I try to rearrange the equation I think I am doing something wrong but I am not sure what exactly.

This is the equation: I am trying to rearrange:

[tex]R^2 = 1-\binom{RSS}{TSS}[/tex]

I know the value of TSS should be ~ 1227.78, but I just cannot get this result when I try to rearrange the equation.

To see where I may be going wrong, please see the screenshot of my whiteboard below:

https://i.stack.imgur.com/VN9pD.png

Thank you in advance for your help.
Guest
 

Re: Rearranging an equation to solve for a variable

Postby Guest » Wed Jun 09, 2021 6:09 pm

Is [tex]\begin{pmatrix}a \\ b \end{pmatrix}[/tex] the binomial coefficient?
Guest
 

Re: Rearranging an equation to solve for a variable

Postby Guest » Fri Jun 18, 2021 4:51 pm

Ah, so it is just a fraction!
[tex]R_2= 1- \frac{RSS}{TSS}[/tex] and you want to solve for TSS.

Yes, "clear the fraction" by multiplying both sides by TSS- but you did that incorrectly!

[tex]R_2(TSS)= TSS- RSS[/tex]. You didn't multiplty the "1" by TSS.
[tex]R_2(TSS)- TSS= (R_2- 1)TSS= -RSS[/tex]

[tex]TSS= -\frac{RSS}{R_2- 1}[/tex]

With [tex]R_2= 0.78[/tex] so that [tex]R_2- 1= -0.22[/tex] and [tex]RSS= 246.66[/tex]
[tex]TSS= -\frac{246.66}{-0.22}= 1121.18
Guest
 


Return to Equations



Who is online

Users browsing this forum: No registered users and 2 guests