6.4+21(z-2)=8.5

Solution for 6.4+21(z-2)=8.5 equation:

Simplifying
6.4 + 21(z + -2) = 8.5

Reorder the terms:
6.4 + 21(-2 + z) = 8.5
6.4 + (-2 * 21 + z * 21) = 8.5
6.4 + (-42 + 21z) = 8.5

Combine like terms: 6.4 + -42 = -35.6
-35.6 + 21z = 8.5

Solving
-35.6 + 21z = 8.5

Solving for variable 'z'.

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

Add '35.6' to each side of the equation.
-35.6 + 35.6 + 21z = 8.5 + 35.6

Combine like terms: -35.6 + 35.6 = 0.0
0.0 + 21z = 8.5 + 35.6
21z = 8.5 + 35.6

Combine like terms: 8.5 + 35.6 = 44.1
21z = 44.1

Divide each side by '21'.
z = 2.1

Simplifying
z = 2.1