Can anyone pls help me with this, I don't even know where to start? I can also give Brainliest
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Answer:
x = 50°
Step-by-step explanation:
The triangle has 3 congruent sides and is therefore equilateral.
The 3 angles are then congruent, each 60°
The left angle in the quadrilateral is adjacent to 60° of the triangle
180° - 60° = 120° ← angle inside quadrilateral
The sum of the interior angles of a quadrilateral = 360°
Subtract the sum of the angles from 360° for x
x = 360° - (120 + 90 + 100)° = 360° - 310° = 50°