How do you solve 2^x = 72x=7?

1 Answer
Mar 16, 2016

x~~2.81x2.81

Explanation:

11. Since the left and right sides of the equation do not have the same base, start by taking the log of both sides.

2^x=72x=7

log(2^x)=log(7)log(2x)=log(7)

22. Use the log property, log_color(purple)b(color(red)m^color(blue)n)=color(blue)n*log_color(purple)b(color(red)m)logb(mn)=nlogb(m), to simplify log(2^x)log(2x).

xlog(2)=log(7)xlog(2)=log(7)

33. Solve for xx.

x=log(7)/log(2)x=log(7)log(2)

color(green)(|bar(ul(color(white)(a/a)x~~2.81color(white)(a/a)|)))