Brain Teasers
Squares
The square of one whole number minus the square of another whole number equals 73.
What are the two numbers? This can be done by trial and error but a little mathematical knowledge and maybe some algebra will get the answer fast.
What are the two numbers? This can be done by trial and error but a little mathematical knowledge and maybe some algebra will get the answer fast.
Hint
73 is similar 41,29,19 etc.Answer
The two numbers are 37 & 36. Therefore (37x37)1369 minus (36x36)1296 = 73. The number 73 is a "prime" number i.e. the only two multiples for it are "73" & "1". By algebra, x2-y2 = 73 which is (x+y)(x-y)=73. One of those two numbers must be "1". It can't be x+y (that would be more than "1") so it must be x-y=1. By simple substitution the answer is revealed.Hide Hint Show Hint Hide Answer Show Answer
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