Times 4 because, 5 times 4 is 20, 20 times 4 is 80 and so on.
Answer:

Step-by-step explanation:
Let v be the speed after the collision of both the cars.
Now, momentum is given by: mass × velocity, then by equating the total momentum before and after the collision of the two cars, we get

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⇒
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Thus, they are moving at the velocity of 
Answers:
1. 5(x-6)
2. k-9
3. 10x + 5
4. the quotient of some number and six
5. the quotient of three times a number and five
6. x^5
The answer should be B. you combine the like terms. when it is a negative sign in front of the parenthesis, when removing the parenthesis, every term inside the parenthesis need to change sign, negative to positive, positive to negative.