Average rate a person can quickly walk

Step-by-step explanation:

hello :  

the discriminat of each quadratic equation : ax²+bx+c=0 (a ≠ 0) is :

Δ = b² -4ac

1 )  Δ > 0  the equation has two reals solutions : x =  (-b±√Δ)/2a

2 ) Δ = 0 : one solution : x = -b/2a

3 ) Δ < 0 : no reals solutions

in this exercice  : 6 = x² - 10x

x²-10x-6=0

a = 1    b= -10  c=-6

Δ =(-10)² -4(1)(-6) continu