Answer:
y is equal to nine and two thirds, or 9.666...
Explanation:
To solve this, we first need to know the value of x. We can see though that x + (x - 12) is equal to 180 degrees, so:
x + 5x - 12 = 180
6x = 192
x = 32
Now that we have x, we can use the same rule to solve for y:
3y - 8 = x
3y - 8 = 32
3y = 40
y = 40 / 3
So y = 40/3, or 9 and 2/3
Bonus:
I almost wonder if the question was printed incorrectly, as the answer would have been a nice tidy integer if the other corner was 3y + 8 instead of 3y - 8.
If that were the case we'd have:
3y + 8 = 32
3y = 24
y = 8
A nice clean answer
To be clear, this last bit is NOT the correct answer, just an observation. If the book tells you that eight is the answer, then the question is misprinted.