What is the value of #x# if #log_6 48 = log_6(x + 7) + log_6(x - 1)#?
1 Answer
Mar 6, 2017
Explanation:
Combine the logarithms.
#log_6 48 = log_6 ((x + 7)(x - 1))#
If
#48 = (x + 7)(x - 1)#
#48 = x^2 + 7x - x - 7#
#48 = x^2 + 6x- 7#
#0 = x^2 + 6x - 55#
#0 = (x+ 11)(x -5)#
#x = -11 and 5#
Practice Exercises
- Solve the following equations using
#log_a n - log_a m = log_a(n/m)# and#log_a m + log_a n = log_a (m * n)# .
a)
b)
Answers:
a)
b)
Hopefully this helps, and good luck!