Answer: Rounded, the diagonal is 4.6 feet
Step-by-step explanation: Use the Pythagorean Theorem: c² = a² + b²
Then take the square root of c² to find the length
2.25² =5.0625 This is a²
4² = 16 This is b² Add a² + b² to get c²
5.o625 + 16 = 21.0625 This is c²
√21.0625 = 4.589389938 This is the square root.
Round this to common measurements or "significant digits" 4.6 feet.