Answer:
The name given to the shaded region would be the positive interval because all f(x) values in that region are positive.
Almost all correct except two. Please check corrected image.
Hello :
the consecutive room numbers are : n , n+1
n(n+1) =420
n²+n -420 = 0
the discriminant delta = b² - 4ac ( a = 1 and b = 1 and c = - 420
delta = (1)²-4(1)(-420) =1681= 41²
n = (-1 -41)/2 ( refused negatif number)
or
n = (-1+41)/2 =20
<span> the room numbers.are : 20 , 21</span>