Find x if 3^2x=80. (exponential equation)

Question

kc_kennylau · Answer

You sure it's 80 or it's 81? :)

anonymous · Answer

Yeah i'm sure
that's what our teacher gave us. :3 i argued with my teacher about the given. She told me that it's impossible that it doesn't have any answer.

kc_kennylau · Answer

well it does have answer

anonymous · Answer

sure? How? :3

kc_kennylau · Answer

1.9943462675018784577975744325248419067531374635967857002677550850751165408573425219501419339786682368419567250641465693335602001489692922548539925528345025117590064752650748654377740446739218532011106869021704748268524513138396910098066920226235999637423486793746789774058787144708439106855578161035768359063190479731227145366381621212224825596256834464008369740368264390765106723045345441593424734009596543847032073101886329312288576345721079963663728671800770584074532666015375997138954510343272901574902237136300580542294023991233632609575380792589030945601139941675845017638225465272229145120358531120956768813408834418350080343276700772839239463305117621054845592858163473507623530280123995888057911525108999282744973240052959290443642464615161733727611470284736845779887195099799272066060889824208267837262139162016110452047798289452659708388048554886341335595840665265478379553775252651975143181907350348128143280252860463996288228695706579452475956115770221030659718430188742164863429154021782589723007552547319518068508175637200997493899610616993571996339664772251104015139895365889581376793345359285705771845713121790436995738127703166354479165646693213853618535806639453901104889594269120016157557187894267021540579955013386932303318087398868455455038096403109313682395626487529518410195295697620388087191196251206748585168744931250756415712614180531077547851782695729106264079030933354337591557055653536720032626644073162555185579155313764376132561292452425607849114399323233835905503892338753638908720606786490412194834288571683636013696673745303940383626965130855232360111536687159401944042838026455257290311195231838902918107933372422370542663967561227883680620858564345543889867972768681011314027618254923360581934874121141550120540657864771248423596501527466944642049404766360075288842016848652878807771698093502249006419770739797193204675269872505819032906534097216947691942085939097895682761139699549103350476719076685419584452469450724271500950301227684372926521281677671191674975129821668226861720685822465188263235424554557182576469301840960795961062419776299038563026246385794208773121972334784279323253885836810319923270136432150856475623821360253093851904473934399691097460866742557523777645314210046957300860724884809872342877641227538099529953030191975538951771074249317449543229525450856405198724688204366121640662840094780201948581723200935840046922489020114001625435038954083406951801653070556708894183128728793784183693864747107211339811833131865541468449469942667452077619137993105455657343427080876752323421265755089159041432852752919292892525969895833435832205737921560802276967786440361005636685050443964047262330209497849213816245824782356192504446897111907317742687251571184121564323822163490815775592136732936253082967707238295485107698171832831472323178720789142188530605864050090138850511510602362511335745577050507487395336021278082805168929129268988684530542803273759183462171925362062398314123395316195214956751249966871345605791176541834982620640189829070827600130863378316238330326531830963105038204662640424435636005710319345352953721545809651710359552441354140291486566034490509784145719574181166493419344445207816431860074010579336032846016627126648821521607388471947362275862873271233581204635779717067589254522064539083717902765769966679053695315695559675917322983844209642330842011670383902702281565227564377928333483726487257922124425165822813344862935171817808011157664122430494339448768518565757296237261678120068104663501282096774147784630362079538554202133541527474016736807417286155699403089099566605652725417466370453001909181043035897623507165752780477187899226851530080577871966533141162090402447177862642221903802703678294033732333772459036947447570212404956936007357364865145215373518335642375543042371176577128730969234185415912271714134726286746283428853230892954274814425822110390605899228722766719162977892791131507093847881344115457510...

kc_kennylau · Answer

http://www.wolframalpha.com/input/?t=crmtb01&f=ob&i=log80%2F(2log3)

anonymous · Answer

our professor in geo, told me to use logarithmic law.

kc_kennylau · Answer

Oh so you have learnt log :)

kc_kennylau · Answer

Then log both sides by base 3
sorry i g2g ttyl (15 mins)

anonymous · Answer

actually, not yet.

anonymous · Answer

okaay. Thanks for the help

kc_kennylau · Answer

im so sorry but g2g