Answer:

Step-by-step explanation:
Write down the problem;

Simplify

Convert so that the fractions have a common denominator; multiply the numerator and denominator of both fractions such that the denominators are equal;

Add the fractions;

Convert to mixed number;

Answer:
5.3
Step-by-step explanation:
Step 1) Add up the three given angles: 125+109+83 = 317
Step 2) Subtract the result (found in step one) from 360
360 - 317 = 43
The reason for the 360 is because for any four-sided polygon, the angles always add up to 360 degrees.
The answer is 43
180(n-2)=n*144 in our casesolving for n we obtain:36n = 360n=10 sidesCHECK!!!!!!!!!!!!!!!!!!!