Answer:
AB = 78
Step-by-step explanation:
Using Pythagoras' identity in the righr triangle.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
AB² = 72² + 30² = 5184 + 900 = 6084 ( take the square root of both sides )
AB = [tex]\sqrt{6084}[/tex] = 78
