error "no solution was found" in solve funcion

[Rudemberg]

Can anyone explain why some equations do not work with the solver command and how can I work around this error?

Here's an example of one of these errors ...

isolating speed is simple in this example but still gives error.

thanks in advance

[Fred_Kohlhepp]

Prime 6 works for me.  

Are the labels correct?

[ValeryOchkov]

[LucMeekes]

Please attach your worksheet showing the offending part.

Without that, it's very hard to find the cause of the error.

Luc

[Werner_E]

Here is what I get in Prime 6, using the new and the old symbolic

I think that Fred's guess is correct and you experience  a problem due to Prime's infamous auto labeling.

Check if both "v" in that region (the one in the formula and the other after "solve") are labeled the same (either both "variable" or both "-")

[-MFra-]

Hi,

I do this way:

[ttokoro]

I have same error in Prime 6.

Prime 5 can solve.

Both can solve.

[-MFra-]

Hi,

a way to solve the problem is the following: