The value of angle 20 is as follows:
m∠20 = 50.9 degrees.
How to find angles when parallel lines are cut by a transversal?
When parallel lines are cut by a transversal, angle relationships are formed. This include corresponding angles, alternate angles , vertical angles etc.
Therefore, line l and m are parallel lines cut by the two transversal.
Hence,
m∠6 ≅ m∠20 (alternate angles)
Therefore, alternate angles are congruent
m∠20 = 2x - 4
m∠19 + m∠20 = 180 (angles on a straight line)
5x - 8 + 2x - 4 = 180
7x - 12 = 180
7x = 180 + 12
7x = 192
x = 192 / 7
x = 27.4285714286
x = 27.43
Therefore,
m∠20 = 2(27.43) - 4
m∠20 = 50.8571428571
m∠20 = 50.9 degrees.
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