-(6-7a)-(10+6a)-20=-(2-7a)+(-a)+1

Solution for -(6-7a)-(10+6a)-20=-(2-7a)+(-a)+1 equation:

Simplifying
-1(6 + -7a) + -1(10 + 6a) + -20 = -1(2 + -7a) + (-1a) + 1
(6 * -1 + -7a * -1) + -1(10 + 6a) + -20 = -1(2 + -7a) + (-1a) + 1
(-6 + 7a) + -1(10 + 6a) + -20 = -1(2 + -7a) + (-1a) + 1
-6 + 7a + (10 * -1 + 6a * -1) + -20 = -1(2 + -7a) + (-1a) + 1
-6 + 7a + (-10 + -6a) + -20 = -1(2 + -7a) + (-1a) + 1

Reorder the terms:
-6 + -10 + -20 + 7a + -6a = -1(2 + -7a) + (-1a) + 1

Combine like terms: -6 + -10 = -16
-16 + -20 + 7a + -6a = -1(2 + -7a) + (-1a) + 1

Combine like terms: -16 + -20 = -36
-36 + 7a + -6a = -1(2 + -7a) + (-1a) + 1

Combine like terms: 7a + -6a = 1a
-36 + 1a = -1(2 + -7a) + (-1a) + 1
-36 + 1a = (2 * -1 + -7a * -1) + (-1a) + 1
-36 + 1a = (-2 + 7a) + (-1a) + 1

Reorder the terms:
-36 + 1a = -2 + 1 + 7a + (-1a)

Combine like terms: -2 + 1 = -1
-36 + 1a = -1 + 7a + (-1a)

Combine like terms: 7a + (-1a) = 6a
-36 + 1a = -1 + 6a

Solving
-36 + 1a = -1 + 6a

Solving for variable 'a'.

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

Add '-6a' to each side of the equation.
-36 + 1a + -6a = -1 + 6a + -6a

Combine like terms: 1a + -6a = -5a
-36 + -5a = -1 + 6a + -6a

Combine like terms: 6a + -6a = 0
-36 + -5a = -1 + 0
-36 + -5a = -1

Add '36' to each side of the equation.
-36 + 36 + -5a = -1 + 36

Combine like terms: -36 + 36 = 0
0 + -5a = -1 + 36
-5a = -1 + 36

Combine like terms: -1 + 36 = 35
-5a = 35

Divide each side by '-5'.
a = -7

Simplifying
a = -7