Complementary means that the two angles sum to 90 degrees.
So based on the problem, let:
1st angle=5x+6
2nd angle=x
Now create an equation.
x+5x+6=90
6x=84
x=14
5x+6=76
answer: 14 degrees and 76 degrees
What linear equation? Your not showing any equation
Answer: for the multiple choice question, its the first one. Then for number of friends it goes, 5,10,15,20 and the cost goes 100,200,300,400. hope this helped!!! xoxo