Answer: 
Step-by-step explanation:
Here the give expression is,

We can write,
( because
)

⇒ Option D is correct.
To evaluate the combination we proceed as follows:
21C3
Given nCk we shall have:
n!/[(n-k)!k!]
thus plugging the values in the expression we get:
21!/[(21-3)!3!]
=21!/(18!×3!)
=1330
Answer: 1330
Answer:
Your solution is (9, 27) or x = 9, y = 27
Step-by-step explanation:
y = 2x + 9
y = 4x - 9
We can see that both of these equations equal y, so we can set them equal to each other.
2x + 9 = 4x - 9
Add 9 to both sides.
2x + 18 = 4x
Subtract 2x from both sides.
18 = 2x
Divide both sides by 2.
9 = x
Now we want to find y. To do this, plug x = 9 back into one of the original equations.
y = 2(9) + 9
Multiply.
y = 18 + 9
Add.
y = 27
Your solution is (9, 27)
Check your answer by plugging x = 9 and y = 27 back into the original equations.
y = 2x + 9
27 = 2(9) + 9
27 = 18 + 9
27 = 27
y = 4x - 9
27 = 4(9) - 9
27 = 36 - 9
27 = 27
Your answer is correct.
Hope this helps!
25,000 x .04 = 1000 a year......
so 7,000 after 7 years
So, in 7 years she'll be making 32,000 a year
Answer:
Step-by-step explanation: