9514 1404 393
Answer:
- x² = y + 16
- 4y - 1 = 7x
- (5, 9)
Step-by-step explanation:
Writing equations from words is mostly a matter of understanding what the English words mean.
If the first number is x, then the square of the first number is x². That is said to be equal to the sum of the second number (y) and 16:
x² = y + 16 . . . . the first equation
The wording "the difference of A and B" is usually intended to be interpreted to mean A-B. Here, we have the difference of 4 times the second number (4y) and 1, so ...
4y -1
This is equal to the first number (x) multiplied by 7, so ...
4y -1 = 7x . . . . the second equation
__
These can be solved a variety of ways. When no method is specified, I like to use a graphing calculator. It shows the only integer solution for this pair of equations is ...
(x, y) = (5, 9)
Answer:
2/5
Step-by-step explanation:
There is an 8/20 chance that the next person will receive a window seat. You simplify that probability to get your answer. 8/20 becomes 2/5. So the answer is 2/5.
Answer:
2 hours 50 minutes
Step-by-step explanation:
Mountain Standard Time is 1 hour earlier than Central Standard Time, so the departure time is equivalent to 6:30 pm in CST.
The time between 6:30 pm and 9:20 pm is 2 hours 50 minutes.
Answer:
a) P(X∩Y) = 0.2
b) 
= 0.16
c) P = 0.47
Step-by-step explanation:
Let's call X the event that the motorist must stop at the first signal and Y the event that the motorist must stop at the second signal.
So, P(X) = 0.36, P(Y) = 0.51 and P(X∪Y) = 0.67
Then, the probability P(X∩Y) that the motorist must stop at both signal can be calculated as:
P(X∩Y) = P(X) + P(Y) - P(X∪Y)
P(X∩Y) = 0.36 + 0.51 - 0.67
P(X∩Y) = 0.2
On the other hand, the probability that he must stop at the first signal but not at the second one can be calculated as:
= P(X) - P(X∩Y)
= 0.36 - 0.2 = 0.16
At the same way, the probability 
that he must stop at the second signal but not at the first one can be calculated as:
= P(Y) - P(X∩Y)
= 0.51 - 0.2 = 0.31
So, the probability that he must stop at exactly one signal is:
