Answer:
2.4
Step-by-step explanation:
Answer:
The answer is 4r² – 9
Denise answer is correct.
Step-by-step explanation:
One of the methods of solving the given equation [(2r – 3)(2r + 3)] is the FOIL method
Using the FOIL method (Used for multiplying binomials)
F stands for first
O stands for outer
I stands for inner
L stands for last
In this method, it means we will first multiply the first terms followed by multiplying the outer term, then multiplying the inner terms and finally, the last terms.
So, for the equation (2r – 3)(2r + 3)
First : (2r)(2r) = 4r²
Outer : (2r)(+3) = 6r
Inner : (–3)(2r) = – 6r
Last : (–3)(+3) = – 9
Adding the results we get
4r² + 6r – 6r – 9 (+6r and – 6r cancels out)
= 4r² – 9
∴ (2r – 3)(2r + 3) = 4r² – 9
Hence, Denise answer is correct
Answer:
the ordered pair is (2,-1)
Step-by-step explanation:
We need to solve the system of equations using elimination method
12x - y = 25 eq(1)
9x + y = 17 eq(2)
Adding eq(1) and eq(2)
12x - y = 25
9x + y = 17
___________
21x = 42
x = 42/21
x= 2
Now, putting value of x in equation 1
12x - y = 25
12(2) -y = 25
24 -y = 25
Adding -24 on both sides
24 -y-24 = 25-24
-y = 25-24
-y = 1
Multiply both sides by -1
y = -1
the value of x = 2 and y = -1
So, the ordered pair is (2,-1)
A fleet of nine taxis is to be dispatched to three airports in such a way that three go to airport A, five go to airport B, and one goes to airport C. In how many distinct ways can this be accomplished?
2.44) Refer to Exercise 2.43. Assume that taxis are allocated to airports at random.
a) If exactly one of the taxis is in need of repair, what is the probability that it is dispatched to airport C?
b) If exactly three of the taxis are in need of repair, what is the probability that every airport receives one of the taxis requiring repairs?
So, my answer to 2.44a is 1/9. Hopefully this is correct at least :)
For 2.44b, my guess was
(3C1)(1/3)(2/3)2 * (5C1)(1/3)(2/3)4 * 1/3
The solutions manual on chegg (which seems to be riddled with errors) says something completely different. Is my calculation correct?
