5y - 16 + 3y + 20 = 180 degrees
Combine like terms on the left side
8y + 4 = 180
Subtract 4 from both sides.
8y = 176
Divide both sides by 8
y = 22
Plug 22 into y for each angle.
3y + 20 = 3(22) + 20 = 66 + 20 = 86 degrees
5y - 16 = 5(22) - 16 = 110 - 16 = 94
The angle opposite 5y - 16 also equals 94 because they are vertical angles.
The angle opposite of 3y + 20 also equals 86 because they are vertical angles
Conditional probablility P(A/B) = P(A and B) / P(B). Here, A is sum of two dice being greater than or equal to 9 and B is at least one of the dice showing 6. Number of ways two dice faces can sum up to 9 = (3, 6), (4, 5), (4, 6), (5, 4), (5, 5), (5, 6), (6, 3), (6, 4), (6, 5), (6, 6) = 10 ways. Number of ways that at least one of the dice must show 6 = (1, 6), (2, 6), (3, 6), (4, 6), (5, 6), (6, 6), (6, 5), (6, 4), (6, 3), (6, 2), (6, 1) = 11 ways. Number of ways of rolling a number greater than or equal to 9 and at least one of the dice showing 6 = (3, 6), (4, 6), (5, 6), (6, 3), (6, 4), (6, 5), (6, 6) = 7 ways. Probability of rolling a number greater than or equal to 9 given that at least one of the dice must show a 6 = 7 / 11
