Answer:
10 < x < 42
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Explanation:
Given a triangle with sides a and b, the third side c is bounded by this compound inequality
b-a < c < b+a
where a < b
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In this case, a = 16 and b = 26, so
b-a < c < b+a
26-16 < x < 26+16
10 < x < 42
I'm using a version of the triangle inequality theorem.
This unknown third side is between 10 cm and 42 cm. The third side cannot equal 10 nor can it equal 42.
