<span>Since the opposite angles are supplementary, an isosceles trapezium is a cyclic quadrilateral. Thus, ABCD is a rectangle as each internal angle is 90°. 8. If the non-parallel sides of a trapezium are equal, prove that it is cyclic.
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A + b + c = 180
a = 2b
b = c + 4
Substitute the b equation into the a equation
a = 2(c + 4)
a = 2c + 8
Substitute equations a and b into the first equation
2c + 8 + c + 4 + c = 180
4c = 168
c = 42
Find the other angles using c
b = 42 + 4
b = 46
a = 2(42) + 8
a = 92
Therefore angle a is 92 degrees, angle b is 46 degrees, and angle c is 42 degrees.
This is a pair of supplementary angles. A supplementary angle means that all angles involved add up to 180 degrees. We know that it is 180 degrees because of the flat line.
Answer: x = 3π/2
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Answer:
Step-by-step explanation:
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