2x + 2(x + 4) = 184 {substituted into perimeter formula}
2x + 2x + 8 = 184 {used distributive property}
4x + 8 = 184 {combined like terms}
4x = 176 {subtracted 8 from each side}
x = 44 {divided each side by 4}
x + 4 = 48 {substituted 44, in for x, into x + 4}