The estimation of the product would be around 15,600 because if you round 5,186, it will become 5,200. multiply that by 3, and that's where you get your answer
Keep in mind that, when the logarithm base is not explicitly written, base 10 is assumed, therefore,
positive = greater than 0.
Therefore we have the inequality:
|add 7 to both sides

We can use vertical opposite angles. Which means the opposite angles where 2 lines intersects is the same.
3x + 50 = 6x - 10 (vert. Opp. Angles)
3x = 6x - 60
-3x = - 60
X = 20°
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)