Ow... this geometry is sure hard!!
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Wait a second. Nope.
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TWO SIDES!!
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ITT!!
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CONVERSE ITT!!
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Converse Isosceles Triangle Theorem!
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Look at the picture I attached.
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Two angles equal... THE SIDES ADJACENT TO IT EQUAL!!
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PERFECTO!!
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Hope I helped!!
Source: I am learning Honors Geometry, near end of course.