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The side lengths are three consecutive odd integer summed up to 51:
(x-2), x and (x+2),
(x-2) + x + (x+2) = 51
3x = 51 ====> x = = 17 ===> the numbers are 17-2 = 15, 17 and 17+2 = 19.
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1. Solved.
2. There is NOTHING more easy than that.
3. The lessons to learn are THESE:
If three consecutive integer sum up to the integer N, then
a) N is a multiple of 3; b) the medium number is ; c) the three numbers are , and .
If three consecutive ODD integers sum up to the integer N, then
a) N is a multiple of 3; b) the medium number is ; c) the three numbers are , and .
If three consecutive EVEN integers sum up to the integer N, then
a) N is a multiple of 3; b) the medium number is ; c) the three numbers are , and .
MEMORIZE it for all your life.