Question

Solve : | -2r - 1 | = 11

Answer 1

Given the equation :

`|-2r-1|=11`

The given absolute function will be written as :

`-2r-1=11,-2r-1=-11`

So, for the first equation :

`\begin{gathered} -2r-1=11 \\ -2r=11+1 \\ -2r=12 \\ r=(12)/(-2)=-6 \end{gathered}`

For the second equation :

`\begin{gathered} -2r-1=-11 \\ -2r=-11+1 \\ -2r=-10 \\ r=(-10)/(-2)=5 \end{gathered}`

So, the answer is : r = { -6 , 5 }