Question

Factorise 24r^2-15r-9 completely. Please explain properly too cause I take a very slow time to understand.

Answer 1

Step-by-step explanation:

24r^2-15r-9

=24r^2-24r+9r-9

=24r(r-1)+9(r-1)

=(r-1)(24r+9)

Answer 2

$24 {r}^{2} - 15r - 9 = 0$

$3(8 {r}^{2} - 5r - 3) = 0$

$8 {r}^{2} - 5r - 3 = 0$

By splitting the middle term , we get

$8 {r}^{2} - 8r + 3r - 3 = 0$

$8r(r - 1) + 3(r - 1) = 0$

$(8r + 3)(r - 1) = 0$

$8r + 3 = 0 \: or \: r - 1 = 0$

$r = \frac{ - 3}{8} \: or \: 1$

I hope it helps you......