Answer :

110x=405

1*x^2 +1*x^1 +0*x^0=4*5^1+0*5^0

x^2+x=4*5

x^2+x=20

x^2+x-20=0

x^2 +5x-4x-20=0

x(x+5)-4(x+5)=20

(x-4)(x+5)=20

x= 4 or -5

But a base cannot be negative so

x=4

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