3a+4c+9c-7b-7a-15c=

Solution for 3a+4c+9c-7b-7a-15c= equation:

Simplifying
3a + 4c + 9c + -7b + -7a + -15c = 0

Reorder the terms:
3a + -7a + -7b + 4c + 9c + -15c = 0

Combine like terms: 3a + -7a = -4a
-4a + -7b + 4c + 9c + -15c = 0

Combine like terms: 4c + 9c = 13c
-4a + -7b + 13c + -15c = 0

Combine like terms: 13c + -15c = -2c
-4a + -7b + -2c = 0

Solving
-4a + -7b + -2c = 0

Solving for variable 'a'.

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

Add '7b' to each side of the equation.
-4a + -7b + 7b + -2c = 0 + 7b

Combine like terms: -7b + 7b = 0
-4a + 0 + -2c = 0 + 7b
-4a + -2c = 0 + 7b
Remove the zero:
-4a + -2c = 7b

Add '2c' to each side of the equation.
-4a + -2c + 2c = 7b + 2c

Combine like terms: -2c + 2c = 0
-4a + 0 = 7b + 2c
-4a = 7b + 2c

Divide each side by '-4'.
a = -1.75b + -0.5c

Simplifying
a = -1.75b + -0.5c