Question

11. Sum of angle measures: 180°

Answer 1

Answer:

$given \: tha \: sum \: is = 180 \\ then \\ n + 4n + 40 = 180 \\ 5n + 40 = 180 \\ 5n = 180 - 40 \\ 5n = 140 \\ n = \frac{140}{5} = 28 \\ n = 28 \\ thank \: you$