-42=-6(-7+a)

Solution for -42=-6(-7+a) equation:

Simplifying
-42 = -6(-7 + a)
-42 = (-7 * -6 + a * -6)
-42 = (42 + -6a)

Solving
-42 = 42 + -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.
-42 + 6a = 42 + -6a + 6a

Combine like terms: -6a + 6a = 0
-42 + 6a = 42 + 0
-42 + 6a = 42

Add '42' to each side of the equation.
-42 + 42 + 6a = 42 + 42

Combine like terms: -42 + 42 = 0
0 + 6a = 42 + 42
6a = 42 + 42

Combine like terms: 42 + 42 = 84
6a = 84

Divide each side by '6'.
a = 14

Simplifying
a = 14