Please Help! Solving a system with substitution + hard algebra

[bubbles930]

Hi guys!

I am in desperate need of help (see image below). Could someone please try this out and see if they get P*?

The T represents tau in case that wasn't clear.



Thanks!

 

[lev888]

Hi guys!

I am in desperate need of help (see image below). Could someone please try this out and see if they get P*?

The T represents tau in case that wasn't clear.

View attachment 18172

Thanks!

If you are getting a different answer please post your work.

 

[Dr.Peterson]

Yes, I do get that expression when I solve for P₁.

You may find the algebra a little easier if you temporarily replace [MATH]l_2 - l_1[/MATH] with A and [MATH]l_1 + l_2[/MATH] with B in each equation, then distribute.

 

[bubbles930]

Yes, I do get that expression when I solve for P₁.

You may find the algebra a little easier if you temporarily replace [MATH]l_2 - l_1[/MATH] with A and [MATH]l_1 + l_2[/MATH] with B in each equation, then distribute.

Thank you for your advice. I gave it another try (pictured below). Would you mind seeing if I have made any errors in my math? Thanks again, this means a lot!

 

[Dr.Peterson]

Looks good. I did it a little differently, mostly by multiplying by 2 twice to clear fractions.