So, here you have to look at the periodic table and see what the molar mass of each molecule composing the water compound

its two hydrogen atom plus an oxygen molecule, making it about 18g per mol.
That said, looking at the mass, we have to ask ourselves, if a mol of water contains 18g of mass, how many moles do we have in 0.5g of water?
We just do a cross multiplication:
2. 4/6 , 6/9
3. 2/4 , 3/6
4. 8/10 , 12/15
5. =
6. >
7. >
8. =
9. =
10. <
11. =
12.
You have to do similar calculations you use in algebra. This is how I get the answer;
First I draw out the algebraic formula 55m • X = 8,484 m (meters) 2 (squared). Then I switch the sign from multiplication to division and switch put numbers 55 and 8,484 in different places and change it to your new formula 8,484/(divided) 55 =X. Then you do the math of 8,484 divided by 55 and get an answer of 154.254545. But you can just leave it at the first 2 digits on the right side of the decimal by rounding 4 down and leaving it at an answer of ~~(<This is your answer after being put together with these tips (you always right your final answer using your formula and plugging in the number that we got from dividing 8,484 by 55;
Final answer ( if they wanted it included in a formula); 8,484/55=X let X=~~154.25
Final answer (if they wanted it as one final number as you answer); ~~154.25
*Hope these tips helped you with this mathematical problem :)
5x + 2y - 2x + 8 = (5x - 2x) + 2y + 8 = 3x + 2y + 8