Question

Which one is correct ?

Answer 1

Give the two exterior angles of 133 and 142, we can deduce that the interior angles are 47 and 38, respectively. In fact, if
`i` and
`e` are the interior and exterior angles, respectively, we have

`i=180-e`

Now, the interior angles of a triangle sum up to 180 degrees. Since we already have angles of 47 and 38 degrees, the missing angle is

`180-47-38=95`

Which implies

`n=180-95=85`