From the triangle

y+z+180-x = 180

y+z = x

1. y = 180 – x

Substituting in the equation, y+z = x

180 + z = 2x

If angle x is obtuse(specifically equal than 120), there is a possibility of this equation holding true.

But there can be a lot of combinations for angle z and y for which this equation will hold good.

Therefore, we cannot clearly predict which side will be longer.

Hence, insufficient.

2. y = z = 60

When this happens, the triangle will become an equilateral triangle where all sides are equal.

This alone is sufficient.(Option B)

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