(a) the given triangle is a isosceles triangle. The two base (non-congruent side) angles (in this case, ∠XYW & ∠XWY) will have the same measurements.
It is given that m∠XYW = 70°, therefore, m∠XWY is also 70°.
Subtract 180 from the two 70° to get m∠X:
180 - (70 + 70) = 180 - 140 = 40°
m∠X = 40° is your answer.
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The given triangle is a equilateral triangle (All sides are congruent). If all sides are congruent, it is a equilateral triangle, and if it is a equilateral triangle, then all measurements of the inside angles are the same, 60°
m∠V = 60°
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