Question

9) 10) 2 20+40. = 60 180-60 = 120 20° 40° 120+40+20 = 180 x = 120I was asked to find the place where there is a question mark which can also be x

Answer 1

The missing side = 21°

Step-by-step explanation:

The sum angles in a triangle is 180°

angles in the larger triangle:

20° + 40° + the third angle = 180°

60° + third angle = 180°

third angle = 180 - 60

third angle = 120°

When two lines cross, their opposite angles are equal. The colours in green are vertical angles. The opposite angle to the third angle we got will also be 120°

The sum of angles in the smaller triangle

120 + 39 + the missing side = 180

159 + the missing side = 180

The missing side = 180 - 159

The missing side = 21°