Question 981451
1)

{{{log(65)+2log(5)-2log(40)}}}


{{{log(65)+log(5^2)-log(40^2)}}}


{{{log((65*25))-log(1600)}}}


{{{log(((65*25)/1600))}}}


{{{log(((65*cross(25)1)/cross(1600)64))}}}


{{{log((65/64))}}}


2)

{{{log(4)+10 log(7)-log(y)=1}}}........... find {{{y}}}

{{{log(4)+log(7^10)-log(y)=1}}}

{{{log(4*7^10)-log(y)=1}}}........{{{1=log(10)}}}


{{{log(((4*7^10)/y))=log(10)}}}...since log same, we have


{{{(4*7^10)/y=10}}}


{{{4*7^10=10y}}}


{{{y=(4*7^10)/10}}}


{{{y=(2*7^10)/5}}}


{{{y=(2*282475249)/5}}}


{{{y = 564950498/5}}}