Water is a polar molecule, meaning the covalent bonds in it share electrons unequally. They spend more time around the oxygen, making it positive and the hydrogens negative. This helps water stick to surfaces, a property called adhesion. The hydrogens of one molecule are also attracted to the oxygens of another. This is called cohesion, and it helps water form droplets
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 :)
Answer:
Its single - displacement.
Explanation: