Answer:
AB = 18, CD = 16
Step-by-step explanation:
The 3 segments make the whole line , that is
AB + BC + CD = AD , substitute values
AB + 20 + (BD - BC) = 54
AB + 20 + (36 - 20) = 54
AB + 20 + 16 = 54
AB + 36 = 54 ( subtract 36 from both sides )
AB = 18
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BC + CD = BD , substitute values
20 + CD = 36 ( subtract 20 from both sides )
CD = 16
