3a+(a-1)=

Solution for 3a+(a-1)= equation:

Simplifying
3a + (a + -1) = 0

Reorder the terms:
3a + (-1 + a) = 0

Remove parenthesis around (-1 + a)
3a + -1 + a = 0

Reorder the terms:
-1 + 3a + a = 0

Combine like terms: 3a + a = 4a
-1 + 4a = 0

Solving
-1 + 4a = 0

Solving for variable 'a'.

Move all terms containing a to the left, all other terms to the right.

Add '1' to each side of the equation.
-1 + 1 + 4a = 0 + 1

Combine like terms: -1 + 1 = 0
0 + 4a = 0 + 1
4a = 0 + 1

Combine like terms: 0 + 1 = 1
4a = 1

Divide each side by '4'.
a = 0.25

Simplifying
a = 0.25