Chapter 6 - Logarithmic Functions - Chapter Test - Page 543: 5

$x = \frac{\log 23 - \log 4}{\log 2}$ $x \approx 2.52$

$20 = -3+4(2^{x})$ $20 + 3 = 4(2^{x})$ $23 = 4(2^{x})$ $\frac{23}{4} = 2^{x}$ $\log \frac{23}{4} = \log 2^{x}$ $\log \frac{23}{4} = x\log 2$ $x = \frac{\log \frac{23}{4}}{\log 2}$ $x = \frac{\log 23 - \log 4}{\log 2}$ $x \approx 2.52$