@SqSehrish So first double the single number and kerpe it then subtract 1 from numbere and put it in front of the number resulting in double.
E.g. 6x2=12 and 6-1=5 so 125
And 5x2=10 and 5-1=4 so 104
Amd so on you will get 41 which is the answer
@Airaasayss It’s a quadratic equation and it may have two possible answers either b = -4 or b= 3. If you solve ���square of b+ b -12=0 .. simple algebra