Reorder the terms:
75 = 3(-5 + -6n)
75 = (-5 3 + -6n 3)
75 = (-15 + -18n)
Solving
75 = -15 + -18n
Solving for variable 'n'.
Move all terms containing n to the left, all other terms to the right.
Add '18n' to each side of the equation.
75 + 18n = -15 + -18n + 18n
Combine like terms: -18n + 18n = 0
75 + 18n = -15 + 0
75 + 18n = -15
Add '-75' to each side of the equation.
75 + -75 + 18n = -15 + -75
Combine like terms: 75 + -75 = 0
0 + 18n = -15 + -75
18n = -15 + -75
Combine like terms: -15 + -75 = -90
18n = -90
Divide each side by '18'.
n = -5
Simplifying
n = -5
Hope that helps
