11. Sum of angle measures: 180°
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Answer:
[tex]given \: tha \: sum \: is = 180 \\ then \\ n + 4n + 40 = 180 \\ 5n + 40 = 180 \\ 5n = 180 - 40 \\ 5n = 140 \\ n = \frac{140}{5} = 28 \\ n = 28 \\ thank \: you[/tex]
Answer:
[tex]given \: that \: sum \: of \: angle \: measur = 180 \\ 40 + n + 4n = 180 \\ 40 + 5n = 180 \\ 5n = 180 - 40 \\ 5n = 140 \\ n = \frac{140}{5} \\ n = 28 \\ [/tex]