since no base is stated, assume the base is 10
remember
[tex]log_a(b)=c[/tex] trasnlates to [tex]a^c=b[/tex] so
[tex]log_{10}(7x+3)=2[/tex] trasnlates to [tex]10^2=7x+3[/tex]
10^2=7x+3
100=7x+3
minus 3 both sides
97=7x
divide by 7 both sides
97/7=x
13.8571=x
13.857=x
