5r2 plus 12r equals -4r2-4

Answer 1

To answer a quadratic like this, st everything equal to zero.

5r^2+12r=-4r^2-4

9r^2+12r+4=0

Ask yourself what two numbers add to get 12 that multiply to get 9*4=36

1*36 no

2*18 no

3*12 no

4*9 no

6*6 yes

(3r+2)(3r+2) The first and last multiply to get 6 and the outside and inside multiply to get 6. That's (3r+)^2