-4.2=-2.1f

Solution for -4.2=-2.1f equation:

Simplifying
-4.2 = -2.1f

Solving
-4.2 = -2.1f

Solving for variable 'f'.

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

Add '2.1f' to each side of the equation.
-4.2 + 2.1f = -2.1f + 2.1f

Combine like terms: -2.1f + 2.1f = 0.0
-4.2 + 2.1f = 0.0

Add '4.2' to each side of the equation.
-4.2 + 4.2 + 2.1f = 0.0 + 4.2

Combine like terms: -4.2 + 4.2 = 0.0
0.0 + 2.1f = 0.0 + 4.2
2.1f = 0.0 + 4.2

Combine like terms: 0.0 + 4.2 = 4.2
2.1f = 4.2

Divide each side by '2.1'.
f = 2

Simplifying
f = 2