Answer:
Consider the complete question is,
'The odds in favor of frank McKinney winning a hot dog eating contest are 2:9,
- Determine the probability that Frank will win the contest,
- Determine the probability that Frank will not win the contest'
Solution :
We know that,
Odds in favor : the ratio of the number of ways that an outcome can occur compared to how many ways it cannot occur.
We have,

So, total outcomes = 2 + 9 = 11,

Thus, the probability that Frank will win the contest = 
And,
The probability that Frank will win the contest = 
To solve this equation simply find 2 numbers that multiply to give -4 and add also to give 3, these numbers are 4 and -1. Since 4 • -1 = -4 and 4 + -1 = 3.
X^2 + 3x - 4 = 0
(X - 1)(X + 4) = 0
X = -4 and X = 1 in ascending order.
Let, the speed of boat = x
Speed of current = y
So, x + y = 280/7
x + y = 40 ---- first equation
x - y = 280/14
x - y = 20
x = 20 + y
Substitute this value of x in first equation,
20 + y + y = 40
2y = 40 - 20
y = 20/2
y = 10
Substitute this in first equation,
x + 10 = 40
x = 30
In short, Speed of Boat = 30 mph, & speed of current = 10 mph
Hope this helps!
Answer:
Step-by-step explanation:
2x(4x -6)
8x^2 - 12x
the answer is c