Answer:
x = 5
Explanation:
The opposite sides of a rectangle are equal , then perimeter
2(- 2x - 6) + 2(4x + 4) = 16 ← distribute parenthesis and simplify left side
- 4x - 12 + 8x + 8 = 16
4x - 4 = 16 ( add 4 to both sides )
4x = 20 ( divide both sides by 4 )
x = 5