(2k+1)(k-4)=

Solution for (2k+1)(k-4)= equation:

Simplifying
(2k + 1)(k + -4) = 0

Reorder the terms:
(1 + 2k)(k + -4) = 0

Reorder the terms:
(1 + 2k)(-4 + k) = 0

Multiply (1 + 2k) * (-4 + k)
(1(-4 + k) + 2k * (-4 + k)) = 0
((-4 * 1 + k * 1) + 2k * (-4 + k)) = 0
((-4 + 1k) + 2k * (-4 + k)) = 0
(-4 + 1k + (-4 * 2k + k * 2k)) = 0
(-4 + 1k + (-8k + 2k2)) = 0

Combine like terms: 1k + -8k = -7k
(-4 + -7k + 2k2) = 0

Solving
-4 + -7k + 2k2 = 0

Solving for variable 'k'.

Factor a trinomial.
(-1 + -2k)(4 + -1k) = 0

Subproblem 1
Set the factor '(-1 + -2k)' equal to zero and attempt to solve:

Simplifying
-1 + -2k = 0

Solving
-1 + -2k = 0

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

Add '1' to each side of the equation.
-1 + 1 + -2k = 0 + 1

Combine like terms: -1 + 1 = 0
0 + -2k = 0 + 1
-2k = 0 + 1

Combine like terms: 0 + 1 = 1
-2k = 1

Divide each side by '-2'.
k = -0.5

Simplifying
k = -0.5
Subproblem 2
Set the factor '(4 + -1k)' equal to zero and attempt to solve:

Simplifying
4 + -1k = 0

Solving
4 + -1k = 0

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

Add '-4' to each side of the equation.
4 + -4 + -1k = 0 + -4

Combine like terms: 4 + -4 = 0
0 + -1k = 0 + -4
-1k = 0 + -4

Combine like terms: 0 + -4 = -4
-1k = -4

Divide each side by '-1'.
k = 4

Simplifying
k = 4
Solution
k = {-0.5, 4}