Answer:
The length and width are
r-11 and r+5
Step-by-step explanation:
The given trinomial is
[tex] {r}^{2} - 6r - 55[/tex]
To factor, we need to split the middle term to get:
[tex]{r}^{2} - 11r + 5r - 55[/tex]
We now factor by grouping to obtain;
[tex]{r}(r- 11) + 5(r - 11)[/tex]
We collect common factors again to get:
[tex](r- 11)(r + 5)[/tex]
Therefore the length and width are
r-11 and r+5
