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nika2105 [10]
3 years ago
6

What is 30-9x2*2-21-4+4

Chemistry
1 answer:
IgorC [24]3 years ago
5 0
Answer:
9 (1-2x²)

Explanation:
The given expression is:
30 - 9x²*2 - 21 - 4 + 4
The first step is to compute the multiplication. This will give:
30 - 18x² - 21 - 4 + 4
Then, we will add like terms as follows:
(30-21-4+4) - 18x²
= 9 - 18x²
Finally, we can take the 9 as a common factor from both terms, this will give:
9 (1-2x²)

Hope this helps :)

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