<u>Answer:</u>
<u>Step-by-step explanation:</u>
We can use the following rule of surds to solve the problem:
,
which means that when multiplying two numbers with the same bases, we can simply add their powers while keeping the base the same.
Applying this rule:

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Answer:
These numbers are not irrational .
Step-by-step explanation:
They are all whole numbers with no decimal points and ongoing numbers.
The sum of -5a and 3 is greater than 1.
Answer: 98.1%
Explanation:
A 10% sale means that the post-sale price of the item is now 90%, or 0.9 of the original cost of the item. We then apply 9% sales tax by multiplying the 0.9 by 109%, or 1.09. 0.9 * 1.09 = .981, so the total cost of the item is 98.1% of the original pre-sale sticker price.
For percentage problems that do not deal with a specific starting number, it is always helpful to plug in 100 for the starting number. Here, we would then have a post-sale price of 90 dollars, and if we calculate the sales tax for the 90-dollar item it would be 90 * 0.09 = $8.10. THis gives us a total cost of 90 + 8.10 = $98.10, or 98.1% of the original 100-dollar price.