Answer:
a = 3
Step-by-step explanation:
Using Pythagoras' identity in the right triangle.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
a² + 8² = ([tex]\sqrt{73}[/tex] )²
a² + 64 = 73 ( subtract 64 from both sides )
a² = 9 ( take the square root of both sides )
a = [tex]\sqrt{9}[/tex] = 3
