Find the sum and express it in simplest form. (-a + 5c) + (-7a + 2c = 3)

If you would like to see my work, here you are:

Remove parenthesis around (-1a + 5c)

-1a + 5c + (-7a + 2c + 3) = 0

Reorder the terms:

-1a + 5c + (3 + -7a + 2c) = 0

Remove parenthesis around (3 + -7a + 2c)

-1a + 5c + 3 + -7a + 2c = 0

Reorder the terms:

3 + -1a + -7a + 5c + 2c = 0

Combine like terms: -1a + -7a = -8a

3 + -8a + 5c + 2c = 0

Combine like terms: 5c + 2c = 7c

3 + -8a + 7c = 0

Solving

3 + -8a + 7c = 0

Solving for variable 'a'.

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

Add '-3' to each side of the equation.

3 + -8a + -3 + 7c = 0 + -3

Reorder the terms:

3 + -3 + -8a + 7c = 0 + -3

Combine like terms: 3 + -3 = 0

0 + -8a + 7c = 0 + -3
-8a + 7c = 0 + -3

Combine like terms: 0 + -3 = -3

-8a + 7c = -3

Add '-7c' to each side of the equation.

-8a + 7c + -7c = -3 + -7c

Combine like terms: 7c + -7c = 0

-8a + 0 = -3 + -7c
-8a = -3 + -7c

Divide each side by '-8'.

a = 0.375 + 0.875c

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answer: the answer is   graph (a)