Question

What is the solution to the equation 14 x - 3 = 21 ? (1 points)

Answer 1

I got this.... but this is not an option.1.71428571429

Answer 2

The answer is x = 4.154

Our expression is $14^{x-3} =21$
Logarith both sides of the expression:
$log(14^{x-3}) =log(21)$
Since $log( x^{a}) = a*log(x)$, then $log( 14^{x-3}) = (x-3)*log(14)$

Back to our expression:
$(x-3)*log(14)=log(21)$
$x-3 = \frac{log(21)}{log(14)}$
$x-3= \frac{1.322}{1.146}$
$x -3 = 1.154 \\ x = 3 + 1.154 \\ x = 4.154$