There are ten kids in a class. when any two meet, each says “hi” to the other and the answer “hi” follows. before the class starts, how many times would one hear the word “hi”?

3 ft

step-by-step explanation:

since the triangle is right use pythagoras' identity to solve for a

the square on the hypotenuse is equal to the sum of the squares on the other two sides, that is

a² + 8² = ( )²

a² + 64 = 73 ( subtract 64 from both sides )

a² = 9 ( take the square root of both sides )

a = = 3