-(a-5b)+(4a+7b)=

Solution for -(a-5b)+(4a+7b)= equation:

Simplifying
-1(a + -5b) + (4a + 7b) = 0
(a * -1 + -5b * -1) + (4a + 7b) = 0
(-1a + 5b) + (4a + 7b) = 0

Remove parenthesis around (4a + 7b)
-1a + 5b + 4a + 7b = 0

Reorder the terms:
-1a + 4a + 5b + 7b = 0

Combine like terms: -1a + 4a = 3a
3a + 5b + 7b = 0

Combine like terms: 5b + 7b = 12b
3a + 12b = 0

Solving
3a + 12b = 0

Solving for variable 'a'.

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

Add '-12b' to each side of the equation.
3a + 12b + -12b = 0 + -12b

Combine like terms: 12b + -12b = 0
3a + 0 = 0 + -12b
3a = 0 + -12b
Remove the zero:
3a = -12b

Divide each side by '3'.
a = -4b

Simplifying
a = -4b