(5-m)(2m-8)=3m

Solution for (5-m)(2m-8)=3m equation:

Simplifying
(5 + -1m)(2m + -8) = 3m

Reorder the terms:
(5 + -1m)(-8 + 2m) = 3m

Multiply (5 + -1m) * (-8 + 2m)
(5(-8 + 2m) + -1m * (-8 + 2m)) = 3m
((-8 * 5 + 2m * 5) + -1m * (-8 + 2m)) = 3m
((-40 + 10m) + -1m * (-8 + 2m)) = 3m
(-40 + 10m + (-8 * -1m + 2m * -1m)) = 3m
(-40 + 10m + (8m + -2m2)) = 3m

Combine like terms: 10m + 8m = 18m
(-40 + 18m + -2m2) = 3m

Solving
-40 + 18m + -2m2 = 3m

Solving for variable 'm'.

Reorder the terms:
-40 + 18m + -3m + -2m2 = 3m + -3m

Combine like terms: 18m + -3m = 15m
-40 + 15m + -2m2 = 3m + -3m

Combine like terms: 3m + -3m = 0
-40 + 15m + -2m2 = 0

Begin completing the square.  Divide all terms by
-2 the coefficient of the squared term: 

Divide each side by '-2'.
20 + -7.5m + m2 = 0

Move the constant term to the right:

Add '-20' to each side of the equation.
20 + -7.5m + -20 + m2 = 0 + -20

Reorder the terms:
20 + -20 + -7.5m + m2 = 0 + -20

Combine like terms: 20 + -20 = 0
0 + -7.5m + m2 = 0 + -20
-7.5m + m2 = 0 + -20

Combine like terms: 0 + -20 = -20
-7.5m + m2 = -20

The m term is -7.5m.  Take half its coefficient (-3.75).
Square it (14.0625) and add it to both sides.

Add '14.0625' to each side of the equation.
-7.5m + 14.0625 + m2 = -20 + 14.0625

Reorder the terms:
14.0625 + -7.5m + m2 = -20 + 14.0625

Combine like terms: -20 + 14.0625 = -5.9375
14.0625 + -7.5m + m2 = -5.9375

Factor a perfect square on the left side:
(m + -3.75)(m + -3.75) = -5.9375

Can't calculate square root of the right side.

The solution to this equation could not be determined.