Answer :
If [tex]221_x=25_{10}[/tex], then
[tex]2x^2 + 2x + 1 = 25[/tex]
Solve for x :
[tex]2x^2+2x-24=0 \\\\ x^2 + x - 12 = 0 \\\\ (x+4)(x-3) = 0 \\\\ \boxed{x = -4 \text{ or }x=3}[/tex]
(Yes, bases can be negative.)
If [tex]221_x=25_{10}[/tex], then
[tex]2x^2 + 2x + 1 = 25[/tex]
Solve for x :
[tex]2x^2+2x-24=0 \\\\ x^2 + x - 12 = 0 \\\\ (x+4)(x-3) = 0 \\\\ \boxed{x = -4 \text{ or }x=3}[/tex]
(Yes, bases can be negative.)