Cos 210° = cos ( 180° + 30° ) - cos 30° = - √3/2
let's firstly convert the mixed fractions to improper fractions and then to do away with the denominators, let's multiply both sides by the LCD of all denominators.
![\stackrel{mixed}{1\frac{3}{4}}\implies \cfrac{1\cdot 4+3}{4}\implies \stackrel{improper}{\cfrac{7}{4}} \\\\[-0.35em] ~\dotfill\\\\ \cfrac{7}{4}-\cfrac{4}{5}=\cfrac{35}{20}-\boxed{?}\implies \stackrel{\textit{multipling both sides by }\stackrel{LCD}{20}}{20\left( \cfrac{7}{4}-\cfrac{4}{5} \right)=20\left( \cfrac{35}{20}-\boxed{?} \right)} \\\\\\ 35-16=35-20\boxed{?}\implies 19=35-20\boxed{?}\implies -16=-20\boxed{?} \\\\\\ \cfrac{-16}{-20}=\boxed{?}\implies \cfrac{4}{5}=\boxed{?}](https://tex.z-dn.net/?f=%5Cstackrel%7Bmixed%7D%7B1%5Cfrac%7B3%7D%7B4%7D%7D%5Cimplies%20%5Ccfrac%7B1%5Ccdot%204%2B3%7D%7B4%7D%5Cimplies%20%5Cstackrel%7Bimproper%7D%7B%5Ccfrac%7B7%7D%7B4%7D%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Ccfrac%7B7%7D%7B4%7D-%5Ccfrac%7B4%7D%7B5%7D%3D%5Ccfrac%7B35%7D%7B20%7D-%5Cboxed%7B%3F%7D%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Bmultipling%20both%20sides%20by%20%7D%5Cstackrel%7BLCD%7D%7B20%7D%7D%7B20%5Cleft%28%20%5Ccfrac%7B7%7D%7B4%7D-%5Ccfrac%7B4%7D%7B5%7D%20%5Cright%29%3D20%5Cleft%28%20%5Ccfrac%7B35%7D%7B20%7D-%5Cboxed%7B%3F%7D%20%5Cright%29%7D%20%5C%5C%5C%5C%5C%5C%2035-16%3D35-20%5Cboxed%7B%3F%7D%5Cimplies%2019%3D35-20%5Cboxed%7B%3F%7D%5Cimplies%20-16%3D-20%5Cboxed%7B%3F%7D%20%5C%5C%5C%5C%5C%5C%20%5Ccfrac%7B-16%7D%7B-20%7D%3D%5Cboxed%7B%3F%7D%5Cimplies%20%5Ccfrac%7B4%7D%7B5%7D%3D%5Cboxed%7B%3F%7D)
Answer:
It should be the second one 4,18,6
Step-by-step explanation:
Let me know if that is right . . .
Hope this helps!
Answer:
You need to buy 5 bags of flour
Step-by-step explanation:
Each bag is 500g and needs 2.5kg.
If we replace 2.5kg it goes to 2500g.
2500g / 500g = 5 bags
The answer is -65.6 because the negative sign is on the out side of the absolute value signs.
