Question

what is 4(5z-1)-5(z+2)=2(z+1)

Answer 1

Is the last term supposed to be (z = 1) or (z - 1)?

Answer 2

z+1

Answer 3

Oh okay. Well then..
4(5z - 1) - 5(z + 2) = 2(z + 1)

Multiply the terms using distributive property to get:
20z - 4 - (5z + 10) = 2z + 2 (the minus sign in front of the parenthesis makes them the opposite signs)

20z - 4 - 5z - 10 = 2z + 2
now move the term 2z over to the other side of the equation
20z - 4 - 5z - 10 - 2z = 2

combine like terms:
(20z - 5z - 2z) + (-4 - 10) = 2
13z - 14 = 2

solve for z:
13z = 16
z = 1.2 or 16/13