Please help I don't understand this. (will mark brainliest)
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That is an isosceles triangle since the 2 sides are the same length. If those 2 sides are the same length, by the Isosceles Triangle Theorem, the angles across from those sides are congruent to each other. That means that both those base angles measure whatever x is. According to the Triangle Angle-sum Theorem, the angles of a triangle all add up to equal 180. We have the vertex angle as 38 degrees, meaning that there is 180 - 38 degrees left to split between the 2 base angles. 180 - 38 = 142, and 142 divided in half is 71. x measures 71 degrees.