Mathematics
merwholocked
2015-11-10 08:20:27
The product of two consecutive room numbers is 420. find the room numbers.
ANSWERS
tinylilpain
2015-11-10 13:28:45

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  the room numbers.are : 20  , 21

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