How do you solve # log_4 a + log_4 5 = 3#? Precalculus Solving Exponential and Logarithmic Equations Logarithmic Models 1 Answer Alan P. Feb 28, 2016 #a=12.8# Explanation: Things you need to know: [1]#color(white)("XXX")log_bp+log_bq = log_b(pq)# [2]#color(white)("XXX")log_b m = k##color(white)("XXXX")# means #color(white)("XXX")b^k=m# #log_4 a + log_4 5 = log_4 5a = 3# from [1] and given equality #4^3=5a# from [2] #rarr 5a = 64# #rarr a=64/5 = 12.8# 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 1266 views around the world You can reuse this answer Creative Commons License