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m in (-oo:+oo)
3 = (1/8)*(-m-15) // - (1/8)*(-m-15)
3-((1/8)*(-m-15)) = 0
(-1/8)*(-m-15)+3 = 0
3-1/8*(-m-15) = 0
3-1/8*(-m-15) = 0
1/8*m+39/8 = 0
1/8*m+39/8 = 0
1/8*m+39/8 = 0 // - 39/8
1/8*m = -39/8 // : 1/8
m = -39/8/1/8
m = -39
m = -39
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