Respuesta :

Answer:

A = 60°

Step-by-step explanation:

First to find the missing angle you add the three known angles,

90 + 135 + 75 = 300

Then, you subtract, 360 - 300 = 60

So, 360° = 60° + 90° + 135° + 75°

Answer:

A = 60 percent

Step-by-step explanation: