Question

How do you solve `6r^2+5r=-1` using the quadratic formula?

Answer 1

`-6/12` and `-4/12`

Explanation:

Compute `Delta` first. `Delta=b^2-(4ac)` where a=6, b=5 and c=1 in the arranged equation: `6r^2+5r+1=0`

Now `Delta=1=5^2-(4*6*1)`

`sqrt Delta=1`

Now compute rs based on `r=(-b-sqrtDelta)/(2a)` and `r=(-b+sqrtDelta)/(2a)`

`r1=(-5-1)/(2*6)=-6/12` and `r2=(-5+1)/(2*6)=-4/12`

These are the answers: `-6/12` and `-4/12`