Answer:
144°
Step-by-step explanation:
The angles of a decagon add up to 1440°
1440/10=144
<span>2x^2-x=3
</span><span>2x^2-x - 3 = 0
</span><span>(2x - 3)(x + 1) = 0
2x - 3 =0
x = 3/2
x + 1 =0
x = -1
answer
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x = -1 and x = 3/2
the angle c is 90°, it is a right triangle. (you see from the picture).
the sum of the interior angles are 180° (in all triangles)
so
180 - 90 - 29 =
61° (angle A)
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90 + 61 + 29 = 180°