In parallelogram the opposite sides are equal. Therefore we have the equation:
[tex]8a-4=6a+10\ \ \ |+4\\\\8a=6a+14\ \ \ |-6a\\\\2a=14\ \ \ |:2\\\\\boxed{a=7}[/tex]
In the parallelogram, the sum of measures of the angles at one side is 180°. Therefore we have the equation:
[tex](18b-11)+(9b+2)=180\\\\(18b+9b)+(-11+2)=180\\\\27b-9=180\ \ \ |+9\\\\27b=189\ \ \ \ |:27\\\\\boxed{b=7}[/tex]
Answer:
c = a + b → c = 7 + 7 = 14
A. 14
