Answer:
Step-by-step explanation:
Simplifying
(7a + -2b) + -1[2(3a + -1c) + -3(2b + -3c)] = 0
Remove parenthesis around (7a + -2b)
7a + -2b + -1[2(3a + -1c) + -3(2b + -3c)] = 0
7a + -2b + -1[(3a * 2 + -1c * 2) + -3(2b + -3c)] = 0
7a + -2b + -1[(6a + -2c) + -3(2b + -3c)] = 0
7a + -2b + -1[6a + -2c + (2b * -3 + -3c * -3)] = 0
7a + -2b + -1[6a + -2c + (-6b + 9c)] = 0
Reorder the terms:
7a + -2b + -1[6a + -6b + -2c + 9c] = 0
Combine like terms: -2c + 9c = 7c
7a + -2b + -1[6a + -6b + 7c] = 0
7a + -2b + [6a * -1 + -6b * -1 + 7c * -1] = 0
7a + -2b + [-6a + 6b + -7c] = 0
Reorder the terms:
7a + -6a + -2b + 6b + -7c = 0
Combine like terms: 7a + -6a = 1a
1a + -2b + 6b + -7c = 0
Combine like terms: -2b + 6b = 4b
1a + 4b + -7c = 0
Solving
1a + 4b + -7c = 0
Solving for variable 'a'.
Move all terms containing a to the left, all other terms to the right.
Add '-4b' to each side of the equation.
1a + 4b + -4b + -7c = 0 + -4b
Combine like terms: 4b + -4b = 0
1a + 0 + -7c = 0 + -4b
1a + -7c = 0 + -4b
Remove the zero:
1a + -7c = -4b
Add '7c' to each side of the equation.
1a + -7c + 7c = -4b + 7c
Combine like terms: -7c + 7c = 0
1a + 0 = -4b + 7c
1a = -4b + 7c
Divide each side by '1'.
a = -4b + 7c
Simplifying
a = -4b + 7c