3-4-7=a

Solution for 3-4-7=a equation:

Simplifying
3 + -4 + -7 = a

Combine like terms: 3 + -4 = -1
-1 + -7 = a

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

Solving
-8 = a

Solving for variable 'a'.

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

Add '-1a' to each side of the equation.
-8 + -1a = a + -1a

Combine like terms: a + -1a = 0
-8 + -1a = 0

Add '8' to each side of the equation.
-8 + 8 + -1a = 0 + 8

Combine like terms: -8 + 8 = 0
0 + -1a = 0 + 8
-1a = 0 + 8

Combine like terms: 0 + 8 = 8
-1a = 8

Divide each side by '-1'.
a = -8

Simplifying
a = -8