ab+3b-7a-21=

Solution for ab+3b-7a-21= equation:

Simplifying
ab + 3b + -7a + -21 = 0

Reorder the terms:
-21 + -7a + ab + 3b = 0

Solving
-21 + -7a + ab + 3b = 0

Solving for variable 'a'.

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

Add '21' to each side of the equation.
-21 + -7a + ab + 21 + 3b = 0 + 21

Reorder the terms:
-21 + 21 + -7a + ab + 3b = 0 + 21

Combine like terms: -21 + 21 = 0
0 + -7a + ab + 3b = 0 + 21
-7a + ab + 3b = 0 + 21

Combine like terms: 0 + 21 = 21
-7a + ab + 3b = 21

Add '-3b' to each side of the equation.
-7a + ab + 3b + -3b = 21 + -3b

Combine like terms: 3b + -3b = 0
-7a + ab + 0 = 21 + -3b
-7a + ab = 21 + -3b

Reorder the terms:
-21 + -7a + ab + 3b = 21 + -3b + -21 + 3b

Reorder the terms:
-21 + -7a + ab + 3b = 21 + -21 + -3b + 3b

Combine like terms: 21 + -21 = 0
-21 + -7a + ab + 3b = 0 + -3b + 3b
-21 + -7a + ab + 3b = -3b + 3b

Combine like terms: -3b + 3b = 0
-21 + -7a + ab + 3b = 0

The solution to this equation could not be determined.