(-2x^3 +x -5) * (x^3 -3x)
= x^6*(-2*1) +x^4*(-2*-3 +1*1) +x^3*(-5) +x^2*(-3) +x(-5*-3)
= -2x^6 +7x^4 -5x^3 -3x^2 +15x
a is the beggining number and n is the amount of times needed to do this. if is 17 you would need to subtract 7 from the originol number 12 (a) that many times.
10(2x)+x
21x is the original number
12x is the reversed number
24x is the reversed then doubled number
Set up an equation:
24x=21x+9
3x=9
x=3
The original number is 63 and the reversed number is 36, which then is 72 when doubled.