SOLUTION: The square of a number is equal to the sum of 21 and 4 times the number. Find the number

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Question 839856: The square of a number is equal to the sum of 21 and 4 times the number. Find the number
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
N%5E2=21%2B4N
N%5E2-4N-21=0
%28N-7%29%28N%2B3%29=0
Two solutions:
N-7=0
N=7
and
N%2B3=0
N=-3