The given expression is
[tex] T = \frac{3U}{E} [/tex]
In this expression we have to solve for U.
First we have to get rid of E from the denominator, and for that, we have to multiply both sides by E, that is
[tex] TE= 3U [/tex]
Now we need to get rid of 3, and for that, we have to divide both sides by 3, that is
[tex] U = \frac{TE}{3} [/tex]
