Question

How do you solve and write the following in interval notation: `abs(5r + 2)< 18`?

Answer 1

`r<16/5 and r> -4` In interval notation: `(-4,16/5)`

Explanation:

`|5r+2| <18 :. 5r+2 <18 and 5r+2 > -18 or 5r<16 and 5r > -20 or r<16/5 and r > -4 :. -4 < r <16/5` In interval notation: `(-4,16/5)`[Ans]