2(.86+.57y)-5y=21

Solution for 2(.86+.57y)-5y=21 equation:

Simplifying
2(0.86 + 0.57y) + -5y = 21
(0.86 * 2 + 0.57y * 2) + -5y = 21
(1.72 + 1.14y) + -5y = 21

Combine like terms: 1.14y + -5y = -3.86y
1.72 + -3.86y = 21

Solving
1.72 + -3.86y = 21

Solving for variable 'y'.

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

Add '-1.72' to each side of the equation.
1.72 + -1.72 + -3.86y = 21 + -1.72

Combine like terms: 1.72 + -1.72 = 0.00
0.00 + -3.86y = 21 + -1.72
-3.86y = 21 + -1.72

Combine like terms: 21 + -1.72 = 19.28
-3.86y = 19.28

Divide each side by '-3.86'.
y = -4.994818653

Simplifying
y = -4.994818653