Answer:
B
Step-by-step explanation:
It’s B
Answer:
21
Step-by-step explanation:
Add all the numbers together
6+8+2.5+2.5+2=21
Yes, the added zeros are significant. Lets say you are converting 1.23 x 10 to the power of 4. The answer would be 12,300 in which case, if you took away the zeros, the number would be 123, which is an incorrect answer.
Hope this makes sense and helps!
Answer:

Step-by-step explanation:

Let's solve the second equation for a to later on replace it in the first equation.

Now plug this into the first equation.

Distribute the 9

Break down the fraction.

Simplify.

Subtract 

Combine like terms.



Muliply by the reciprocal or inverted fraction next to b.


Now plug this value into any of the equations to find the value of a.

So you wont forget what you wrote and it helps you to figure out the problem. I hope this helps.