90=-6(1+2k)

Solution for 90=-6(1+2k) equation:

Simplifying
90 = -6(1 + 2k)
90 = (1 * -6 + 2k * -6)
90 = (-6 + -12k)

Solving
90 = -6 + -12k

Solving for variable 'k'.

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

Add '12k' to each side of the equation.
90 + 12k = -6 + -12k + 12k

Combine like terms: -12k + 12k = 0
90 + 12k = -6 + 0
90 + 12k = -6

Add '-90' to each side of the equation.
90 + -90 + 12k = -6 + -90

Combine like terms: 90 + -90 = 0
0 + 12k = -6 + -90
12k = -6 + -90

Combine like terms: -6 + -90 = -96
12k = -96

Divide each side by '12'.
k = -8

Simplifying
k = -8