35.9=42.8+a

Solution for 35.9=42.8+a equation:

Simplifying
35.9 = 42.8 + a

Solving
35.9 = 42.8 + 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.
35.9 + -1a = 42.8 + a + -1a

Combine like terms: a + -1a = 0
35.9 + -1a = 42.8 + 0
35.9 + -1a = 42.8

Add '-35.9' to each side of the equation.
35.9 + -35.9 + -1a = 42.8 + -35.9

Combine like terms: 35.9 + -35.9 = 0.0
0.0 + -1a = 42.8 + -35.9
-1a = 42.8 + -35.9

Combine like terms: 42.8 + -35.9 = 6.9
-1a = 6.9

Divide each side by '-1'.
a = -6.9

Simplifying
a = -6.9