Felt appears to be right triangles
A appears to be an equilateral triangle
Substitute first Y for the second Y
So it would be x + x + 6 = -2
Then it would be 2x +6 = -2
Move the 6 over so it would be 2x =-8
Divide by 2 your answer is x = -4
So just add 1/8 and 2/8. add 1 plus 2 and the denominator (bottom number) stays the same so you get 3/8 then subtract 8/8 minus 3/8 so just 8 minus 3 is 5 and the denominator stays the same so you end up with 5/8 so 5/8 of the book remains unread