How do you solve #log_5 (x+10) + log_5 (x-10) = 3#? Precalculus Solving Exponential and Logarithmic Equations Logarithmic Models 1 Answer Vinícius Ferraz Dec 9, 2015 #x in {15}# Explanation: #log_5 [(x+10)(x-10)] = log_5 125# #x^2 - 100 = 125# #x^2 = 225# #x = ± 15# But #x + 10 > 0 and x - 10 > 0# Answer link Related questions What is a logarithmic model? How do I use a logarithmic model to solve applications? What is the advantage of a logarithmic model? How does the Richter scale measure magnitude? What is the range of the Richter scale? How do you solve #9^(x-4)=81#? How do you solve #logx+log(x+15)=2#? How do you solve the equation #2 log4(x + 7)-log4(16) = 2#? How do you solve #2 log x^4 = 16#? How do you solve #2+log_3(2x+5)-log_3x=4#? See all questions in Logarithmic Models Impact of this question 2350 views around the world You can reuse this answer Creative Commons License