5⋅115a+10=57
5⋅115a+105=575aaaDivide both sides by 5
115a+10=575
log(115a+10)=log(575)aaaTake the log of both sides
(5a+10)log11=log(575)aaUse the log rule logxa=alogx
(5a+10)log11log11=log(575)log11aaDivide both sides by log11
5a+10=log(575)log11
aa−10aaa−10aaaSubtract 10 from both sides
5a=log(575)log11−10
5a5=log(575)log11−105aaaDivide both sides by 5
a=−1.797aaaUse a calculator