Answer:
x = 20
Step-by-step explanation:
The three angles make up a straight line.
A straight line has 180 degrees.
x + 3x + 100 = x80 Combine
4x + 100 = 180 Subtract 100 from both sides
4x = 180 - 100
4x = 80 Divide by 4
x = 80/4
x = 20
Me too honestly they give so much work
Remark
If you just want the way this would be written out the answer is

Note
1. The quotient is the answer of a division problem.
2. The number is represented by the letter x
I'm pretty sure it's 28 but sorry if I'm wrong it might be 44
ANSWER
D. 14
EXPLANATION
The ratio of the books in the book case are:
Red:Yellow:Green=3:5:2
The number of yellow books in the book case is 35.
If 5 corresponds to 35, then 2 green books will correspond to a less number of books,
By proportion, because it is going to be less more will divide.
The number of green books in the book case is

