Hey there!
[tex]3p - 1 = 5(p-1)-2(7-2p)
Use the distributive property 
3p - 1= (5)(p)+(5)(-1)+(-2)(7)+(-2)(-2p)
3p - 1 = 5p - 5 - 14 + 4p
3p - 1= 9p - 19 
3p - 9p =-19 + 1 
-6p = 18 
Divide both sides by -6 
-6p/-6 = -18/-6
p = 3 
Best of luck with your studies! [/tex]