Answer:
Approximately 17.88x or 
Step-by-step explanation:
Use pythagorean formula. In a rhombus the diagonals bisect each other and they are perpendicular, so you could have a right triangle with legs of 2x and 4x, the hypoteneuse would then be 
which is approximately 4.47x. In a rhombus all 4 sides are the same, so multiply that by 4 and you get the perimeter. 4(4.47x) = 17.88x or if you simplify the radical instead it's
Answer:
43
Step-by-step explanation:
The first three numbers are perfect squares:
9 = 3²
16 = 4²
25 = 5²
43 is not a perfect square.
