-90=-2(3-7k)

Solution for -90=-2(3-7k) equation:

Simplifying
-90 = -2(3 + -7k)
-90 = (3 * -2 + -7k * -2)
-90 = (-6 + 14k)

Solving
-90 = -6 + 14k

Solving for variable 'k'.

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

Add '-14k' to each side of the equation.
-90 + -14k = -6 + 14k + -14k

Combine like terms: 14k + -14k = 0
-90 + -14k = -6 + 0
-90 + -14k = -6

Add '90' to each side of the equation.
-90 + 90 + -14k = -6 + 90

Combine like terms: -90 + 90 = 0
0 + -14k = -6 + 90
-14k = -6 + 90

Combine like terms: -6 + 90 = 84
-14k = 84

Divide each side by '-14'.
k = -6

Simplifying
k = -6