We don't know whether those two sides are both legs
of the right triangle, or if BC is the hypotenuse.
If AC and BC are both legs, then
AB = √ (AC² + BC²)
= √ (7² + 8²)
= √ (49 + 64) = √ 113 .
If BC is the hypotenuse of the right triangle, then
AB = √ (BC² - AC²)
= √ (8² - 7²)
= √ (64 - 49) = √ 15 .
Answer:
X + 8 = 8 + X is the correct answer
If an event has a probability P of happening, then there is a probability of (1-P) of the event not happening.
In this case the probability of the event is p=20/69.
Then, the probability of the event not happening is:

Answer: the probability of the event not happening is 49/69.
Answer:
there may be 16 but I am not sure