a, b, c - sides of a triangle
a + b > c
a + c > b
b + c > a
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We have a = 5m and b = 11m. Substitute:
5 + 11 > c
16 > c → c < 16
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5 + c > 11 subtract 5 from both sides
c > 6
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11 + c > 5 subtract 11 from both sides
c > -6
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c < 16 and c > 6 and c > -6
Thereofre your answer is 6m < c < 16m
