1/3(p+2)=1/4(p-1)=....

[tex] \frac{p+2}{3} = \frac{p-1}{4} \\ 4(p + 2) = 3(p - 1) \\ 4p + 8 = 3p - 3 \\ p = - 11[/tex]

   1/3(p+2) = 1/4(p-1)
<-> 4(p+2) = 3(p-1)
<-> 4p + 8 = 3p - 3
<-> 4p -3p = -3 - 8
              p = -11