Answer:
Step-by-step explanation:
In order to combine like terms, you have to isolate x and y from one side of the equation.

<u>First, thing you do is remove parentheses.</u>

<u>Solve.</u>
<u>Then, you combine like terms.</u>

<u>Add/subtract the numbers from left to right.</u>
-8z+3.5z=-4.5z
<u>Rewrite the problem down.</u>

<u>Solve.</u>
4.5-1.5=3

- <u>Therefore, the correct answer is 7y+3-4.5z.</u>
I hope this helps, let me know if you have any questions.
Answer:
5n
Step-by-step explanation:
cost of one helmet = $5
let 'n' be the number of person that is n=1,2,3,4........
note that the value of n is always a natural number
therefore the expression = 5n
where 5 is the cost one helmet
n is the number of persons
I think its B but ima have to check again and get back to you
5. After 6 hours, the concentration is halved. After 12 hours, it will be quartered. If the original concentration is 200 nmol, a quarter is 50 nmol.
14. The population doubles after 3 hours, and a day is 24 hours. That means that the original population should be multiplied by
, or
. 3 million times
is 3 * 256 million, or 768 million.
15. The concentration is halved every 8 hours and the original concentration is 100 nmol. So now, how many times do you halve 100 to get to 12.5?
100/2 = 50, 50/2 = 25, 25/2 = 12.5. That's three times. 3 * 8 is 24 hours, or 1 day.