Answer:
I don’t get most of it, but I believe “doubles” means two of the same number added together. For example, 9+9 is a double. I think “doubles +1” means a double and add one. For example, 6+6+1. If I were your sister, I would write “9+9 = 18” for doubles and “6+6+1 = 13” for doubles +1.
I hope I helped!
Step-by-step explanation:
3a^2+24a+45=0
×3/3( first ×3)
9a^2+24(3a)+135=0
(3a+15)(3a+9)=0
now /3
3(a+5)(a+3)
a=-5✓
a=-3✓
Yes you see 11-3 is 8 so +11-3=8
