Respuesta :

jaimitoM

The sum of angles of a triangle equals the straight angle (180°), therefore:

3x + 12x + 1 + 16x - 7 = 180

31x-6=180

31x = 180 + 6

31x = 186

x = 186/31

x = 6

Then, the angles are:

3(6) = 18°

16*6 - 7 = 89°

12(6) +1 = 73°