Answer:
82 cm
Step-by-step explanation:
In rectangles diagonals are equal and bisect each other
AO = BO
5x + 1 = 4x + 9
Subtract 1 from both sides
5x = 4x + 9 -1
5x = 4x + 8
Subtract 4x from both the sides
5x - 4x = 8
x = 8
AO = 5x + 1
= 5*8 +1
= 40 + 1
AO= 41 cm
Diagonal = 2*41 = 82 cm
