See tutors' answers!

Algebra ->  Tutoring on algebra.com -> See tutors' answers!      Log On


   
By Tutor
 | By Problem Number | 

Tutor:
New! Get regular updates about newly solved problems via algebra.com's RSS system.

Recent problems solved by 'Alan3354'

Alan3354 answered: 30973 problems
Jump to solutions: 0..29 , 30..59 , 60..89 , 90..119 , 120..149 , 150..179 , 180..209 , 210..239 , 240..269 , 270..299 , 300..329 , 330..359 , 360..389 , 390..419 , 420..449 , 450..479 , 480..509 , 510..539 , 540..569 , 570..599 , 600..629 , 630..659 , 660..689 , 690..719 , 720..749 , 750..779 , 780..809 , 810..839 , 840..869 , 870..899 , 900..929 , 930..959 , 960..989 , 990..1019 , 1020..1049 , 1050..1079 , 1080..1109 , 1110..1139 , 1140..1169 , 1170..1199 , 1200..1229 , 1230..1259 , 1260..1289 , 1290..1319 , 1320..1349 , 1350..1379 , 1380..1409 , 1410..1439 , 1440..1469 , 1470..1499 , 1500..1529 , 1530..1559 , 1560..1589 , 1590..1619 , 1620..1649 , 1650..1679 , 1680..1709 , 1710..1739 , 1740..1769 , 1770..1799 , 1800..1829 , 1830..1859 , 1860..1889 , 1890..1919 , 1920..1949 , 1950..1979 , 1980..2009 , 2010..2039 , 2040..2069 , 2070..2099 , 2100..2129 , 2130..2159 , 2160..2189 , 2190..2219 , 2220..2249 , 2250..2279 , 2280..2309 , 2310..2339 , 2340..2369 , 2370..2399 , 2400..2429 , 2430..2459 , 2460..2489 , 2490..2519 , 2520..2549 , 2550..2579 , 2580..2609 , 2610..2639 , 2640..2669 , 2670..2699 , 2700..2729 , 2730..2759 , 2760..2789 , 2790..2819 , 2820..2849 , 2850..2879 , 2880..2909 , 2910..2939 , 2940..2969 , 2970..2999 , 3000..3029 , 3030..3059 , 3060..3089 , 3090..3119 , 3120..3149 , 3150..3179 , 3180..3209 , 3210..3239 , 3240..3269 , 3270..3299 , 3300..3329 , 3330..3359 , 3360..3389 , 3390..3419 , 3420..3449 , 3450..3479 , 3480..3509 , 3510..3539 , 3540..3569 , 3570..3599 , 3600..3629 , 3630..3659 , 3660..3689 , 3690..3719 , 3720..3749 , 3750..3779 , 3780..3809 , 3810..3839 , 3840..3869 , 3870..3899 , 3900..3929 , 3930..3959 , 3960..3989 , 3990..4019 , 4020..4049 , 4050..4079 , 4080..4109 , 4110..4139 , 4140..4169 , 4170..4199 , 4200..4229 , 4230..4259 , 4260..4289 , 4290..4319 , 4320..4349 , 4350..4379 , 4380..4409 , 4410..4439 , 4440..4469 , 4470..4499 , 4500..4529 , 4530..4559 , 4560..4589 , 4590..4619 , 4620..4649 , 4650..4679 , 4680..4709 , 4710..4739 , 4740..4769 , 4770..4799 , 4800..4829 , 4830..4859 , 4860..4889 , 4890..4919 , 4920..4949 , 4950..4979 , 4980..5009 , 5010..5039 , 5040..5069 , 5070..5099 , 5100..5129 , 5130..5159 , 5160..5189 , 5190..5219 , 5220..5249 , 5250..5279 , 5280..5309 , 5310..5339 , 5340..5369 , 5370..5399 , 5400..5429 , 5430..5459 , 5460..5489 , 5490..5519 , 5520..5549 , 5550..5579 , 5580..5609 , 5610..5639 , 5640..5669 , 5670..5699 , 5700..5729 , 5730..5759 , 5760..5789 , 5790..5819 , 5820..5849 , 5850..5879 , 5880..5909 , 5910..5939 , 5940..5969 , 5970..5999 , 6000..6029 , 6030..6059 , 6060..6089 , 6090..6119 , 6120..6149 , 6150..6179 , 6180..6209 , 6210..6239 , 6240..6269 , 6270..6299 , 6300..6329 , 6330..6359 , 6360..6389 , 6390..6419 , 6420..6449 , 6450..6479 , 6480..6509 , 6510..6539 , 6540..6569 , 6570..6599 , 6600..6629 , 6630..6659 , 6660..6689 , 6690..6719 , 6720..6749 , 6750..6779 , 6780..6809 , 6810..6839 , 6840..6869 , 6870..6899 , 6900..6929 , 6930..6959 , 6960..6989 , 6990..7019 , 7020..7049 , 7050..7079 , 7080..7109 , 7110..7139 , 7140..7169 , 7170..7199 , 7200..7229 , 7230..7259 , 7260..7289 , 7290..7319 , 7320..7349 , 7350..7379 , 7380..7409 , 7410..7439 , 7440..7469 , 7470..7499 , 7500..7529 , 7530..7559 , 7560..7589 , 7590..7619 , 7620..7649 , 7650..7679 , 7680..7709 , 7710..7739 , 7740..7769 , 7770..7799 , 7800..7829 , 7830..7859 , 7860..7889 , 7890..7919 , 7920..7949 , 7950..7979 , 7980..8009 , 8010..8039 , 8040..8069 , 8070..8099 , 8100..8129 , 8130..8159 , 8160..8189 , 8190..8219 , 8220..8249 , 8250..8279 , 8280..8309 , 8310..8339 , 8340..8369 , 8370..8399 , 8400..8429 , 8430..8459 , 8460..8489 , 8490..8519 , 8520..8549 , 8550..8579 , 8580..8609 , 8610..8639 , 8640..8669 , 8670..8699 , 8700..8729 , 8730..8759 , 8760..8789 , 8790..8819 , 8820..8849 , 8850..8879 , 8880..8909 , 8910..8939 , 8940..8969 , 8970..8999 , 9000..9029 , 9030..9059 , 9060..9089 , 9090..9119 , 9120..9149 , 9150..9179 , 9180..9209 , 9210..9239 , 9240..9269 , 9270..9299 , 9300..9329 , 9330..9359 , 9360..9389 , 9390..9419 , 9420..9449 , 9450..9479 , 9480..9509 , 9510..9539 , 9540..9569 , 9570..9599 , 9600..9629 , 9630..9659 , 9660..9689 , 9690..9719 , 9720..9749 , 9750..9779 , 9780..9809 , 9810..9839 , 9840..9869 , 9870..9899 , 9900..9929 , 9930..9959 , 9960..9989 , 9990..10019 , 10020..10049 , 10050..10079 , 10080..10109 , 10110..10139 , 10140..10169 , 10170..10199 , 10200..10229 , 10230..10259 , 10260..10289 , 10290..10319 , 10320..10349 , 10350..10379 , 10380..10409 , 10410..10439 , 10440..10469 , 10470..10499 , 10500..10529 , 10530..10559 , 10560..10589 , 10590..10619 , 10620..10649 , 10650..10679 , 10680..10709 , 10710..10739 , 10740..10769 , 10770..10799 , 10800..10829 , 10830..10859 , 10860..10889 , 10890..10919 , 10920..10949 , 10950..10979 , 10980..11009 , 11010..11039 , 11040..11069 , 11070..11099 , 11100..11129 , 11130..11159 , 11160..11189 , 11190..11219 , 11220..11249 , 11250..11279 , 11280..11309 , 11310..11339 , 11340..11369 , 11370..11399 , 11400..11429 , 11430..11459 , 11460..11489 , 11490..11519 , 11520..11549 , 11550..11579 , 11580..11609 , 11610..11639 , 11640..11669 , 11670..11699 , 11700..11729 , 11730..11759 , 11760..11789 , 11790..11819 , 11820..11849 , 11850..11879 , 11880..11909 , 11910..11939 , 11940..11969 , 11970..11999 , 12000..12029 , 12030..12059 , 12060..12089 , 12090..12119 , 12120..12149 , 12150..12179 , 12180..12209 , 12210..12239 , 12240..12269 , 12270..12299 , 12300..12329 , 12330..12359 , 12360..12389 , 12390..12419 , 12420..12449 , 12450..12479 , 12480..12509 , 12510..12539 , 12540..12569 , 12570..12599 , 12600..12629 , 12630..12659 , 12660..12689 , 12690..12719 , 12720..12749 , 12750..12779 , 12780..12809 , 12810..12839 , 12840..12869 , 12870..12899 , 12900..12929 , 12930..12959 , 12960..12989 , 12990..13019 , 13020..13049 , 13050..13079 , 13080..13109 , 13110..13139 , 13140..13169 , 13170..13199 , 13200..13229 , 13230..13259 , 13260..13289 , 13290..13319 , 13320..13349 , 13350..13379 , 13380..13409 , 13410..13439 , 13440..13469 , 13470..13499 , 13500..13529 , 13530..13559 , 13560..13589 , 13590..13619 , 13620..13649 , 13650..13679 , 13680..13709 , 13710..13739 , 13740..13769 , 13770..13799 , 13800..13829 , 13830..13859 , 13860..13889 , 13890..13919 , 13920..13949 , 13950..13979 , 13980..14009 , 14010..14039 , 14040..14069 , 14070..14099 , 14100..14129 , 14130..14159 , 14160..14189 , 14190..14219 , 14220..14249 , 14250..14279 , 14280..14309 , 14310..14339 , 14340..14369 , 14370..14399 , 14400..14429 , 14430..14459 , 14460..14489 , 14490..14519 , 14520..14549 , 14550..14579 , 14580..14609 , 14610..14639 , 14640..14669 , 14670..14699 , 14700..14729 , 14730..14759 , 14760..14789 , 14790..14819 , 14820..14849 , 14850..14879 , 14880..14909 , 14910..14939 , 14940..14969 , 14970..14999 , 15000..15029 , 15030..15059 , 15060..15089 , 15090..15119 , 15120..15149 , 15150..15179 , 15180..15209 , 15210..15239 , 15240..15269 , 15270..15299 , 15300..15329 , 15330..15359 , 15360..15389 , 15390..15419 , 15420..15449 , 15450..15479 , 15480..15509 , 15510..15539 , 15540..15569 , 15570..15599 , 15600..15629 , 15630..15659 , 15660..15689 , 15690..15719 , 15720..15749 , 15750..15779 , 15780..15809 , 15810..15839 , 15840..15869 , 15870..15899 , 15900..15929 , 15930..15959 , 15960..15989 , 15990..16019 , 16020..16049 , 16050..16079 , 16080..16109 , 16110..16139 , 16140..16169 , 16170..16199 , 16200..16229 , 16230..16259 , 16260..16289 , 16290..16319 , 16320..16349 , 16350..16379 , 16380..16409 , 16410..16439 , 16440..16469 , 16470..16499 , 16500..16529 , 16530..16559 , 16560..16589 , 16590..16619 , 16620..16649 , 16650..16679 , 16680..16709 , 16710..16739 , 16740..16769 , 16770..16799 , 16800..16829 , 16830..16859 , 16860..16889 , 16890..16919 , 16920..16949 , 16950..16979 , 16980..17009 , 17010..17039 , 17040..17069 , 17070..17099 , 17100..17129 , 17130..17159 , 17160..17189 , 17190..17219 , 17220..17249 , 17250..17279 , 17280..17309 , 17310..17339 , 17340..17369 , 17370..17399 , 17400..17429 , 17430..17459 , 17460..17489 , 17490..17519 , 17520..17549 , 17550..17579 , 17580..17609 , 17610..17639 , 17640..17669 , 17670..17699 , 17700..17729 , 17730..17759 , 17760..17789 , 17790..17819 , 17820..17849 , 17850..17879 , 17880..17909 , 17910..17939 , 17940..17969 , 17970..17999 , 18000..18029 , 18030..18059 , 18060..18089 , 18090..18119 , 18120..18149 , 18150..18179 , 18180..18209 , 18210..18239 , 18240..18269 , 18270..18299 , 18300..18329 , 18330..18359 , 18360..18389 , 18390..18419 , 18420..18449 , 18450..18479 , 18480..18509 , 18510..18539 , 18540..18569 , 18570..18599 , 18600..18629 , 18630..18659 , 18660..18689 , 18690..18719 , 18720..18749 , 18750..18779 , 18780..18809 , 18810..18839 , 18840..18869 , 18870..18899 , 18900..18929 , 18930..18959 , 18960..18989 , 18990..19019 , 19020..19049 , 19050..19079 , 19080..19109 , 19110..19139 , 19140..19169 , 19170..19199 , 19200..19229 , 19230..19259 , 19260..19289 , 19290..19319 , 19320..19349 , 19350..19379 , 19380..19409 , 19410..19439 , 19440..19469 , 19470..19499 , 19500..19529 , 19530..19559 , 19560..19589 , 19590..19619 , 19620..19649 , 19650..19679 , 19680..19709 , 19710..19739 , 19740..19769 , 19770..19799 , 19800..19829 , 19830..19859 , 19860..19889 , 19890..19919 , 19920..19949 , 19950..19979 , 19980..20009 , 20010..20039 , 20040..20069 , 20070..20099 , 20100..20129 , 20130..20159 , 20160..20189 , 20190..20219 , 20220..20249 , 20250..20279 , 20280..20309 , 20310..20339 , 20340..20369 , 20370..20399 , 20400..20429 , 20430..20459 , 20460..20489 , 20490..20519 , 20520..20549 , 20550..20579 , 20580..20609 , 20610..20639 , 20640..20669 , 20670..20699 , 20700..20729 , 20730..20759 , 20760..20789 , 20790..20819 , 20820..20849 , 20850..20879 , 20880..20909 , 20910..20939 , 20940..20969 , 20970..20999 , 21000..21029 , 21030..21059 , 21060..21089 , 21090..21119 , 21120..21149 , 21150..21179 , 21180..21209 , 21210..21239 , 21240..21269 , 21270..21299 , 21300..21329 , 21330..21359 , 21360..21389 , 21390..21419 , 21420..21449 , 21450..21479 , 21480..21509 , 21510..21539 , 21540..21569 , 21570..21599 , 21600..21629 , 21630..21659 , 21660..21689 , 21690..21719 , 21720..21749 , 21750..21779 , 21780..21809 , 21810..21839 , 21840..21869 , 21870..21899 , 21900..21929 , 21930..21959 , 21960..21989 , 21990..22019 , 22020..22049 , 22050..22079 , 22080..22109 , 22110..22139 , 22140..22169 , 22170..22199 , 22200..22229 , 22230..22259 , 22260..22289 , 22290..22319 , 22320..22349 , 22350..22379 , 22380..22409 , 22410..22439 , 22440..22469 , 22470..22499 , 22500..22529 , 22530..22559 , 22560..22589 , 22590..22619 , 22620..22649 , 22650..22679 , 22680..22709 , 22710..22739 , 22740..22769 , 22770..22799 , 22800..22829 , 22830..22859 , 22860..22889 , 22890..22919 , 22920..22949 , 22950..22979 , 22980..23009 , 23010..23039 , 23040..23069 , 23070..23099 , 23100..23129 , 23130..23159 , 23160..23189 , 23190..23219 , 23220..23249 , 23250..23279 , 23280..23309 , 23310..23339 , 23340..23369 , 23370..23399 , 23400..23429 , 23430..23459 , 23460..23489 , 23490..23519 , 23520..23549 , 23550..23579 , 23580..23609 , 23610..23639 , 23640..23669 , 23670..23699 , 23700..23729 , 23730..23759 , 23760..23789 , 23790..23819 , 23820..23849 , 23850..23879 , 23880..23909 , 23910..23939 , 23940..23969 , 23970..23999 , 24000..24029 , 24030..24059 , 24060..24089 , 24090..24119 , 24120..24149 , 24150..24179 , 24180..24209 , 24210..24239 , 24240..24269 , 24270..24299 , 24300..24329 , 24330..24359 , 24360..24389 , 24390..24419 , 24420..24449 , 24450..24479 , 24480..24509 , 24510..24539 , 24540..24569 , 24570..24599 , 24600..24629 , 24630..24659 , 24660..24689 , 24690..24719 , 24720..24749 , 24750..24779 , 24780..24809 , 24810..24839 , 24840..24869 , 24870..24899 , 24900..24929 , 24930..24959 , 24960..24989 , 24990..25019 , 25020..25049 , 25050..25079 , 25080..25109 , 25110..25139 , 25140..25169 , 25170..25199 , 25200..25229 , 25230..25259 , 25260..25289 , 25290..25319 , 25320..25349 , 25350..25379 , 25380..25409 , 25410..25439 , 25440..25469 , 25470..25499 , 25500..25529 , 25530..25559 , 25560..25589 , 25590..25619 , 25620..25649 , 25650..25679 , 25680..25709 , 25710..25739 , 25740..25769 , 25770..25799 , 25800..25829 , 25830..25859 , 25860..25889 , 25890..25919 , 25920..25949 , 25950..25979 , 25980..26009 , 26010..26039 , 26040..26069 , 26070..26099 , 26100..26129 , 26130..26159 , 26160..26189 , 26190..26219 , 26220..26249 , 26250..26279 , 26280..26309 , 26310..26339 , 26340..26369 , 26370..26399 , 26400..26429 , 26430..26459 , 26460..26489 , 26490..26519 , 26520..26549 , 26550..26579 , 26580..26609 , 26610..26639 , 26640..26669 , 26670..26699 , 26700..26729 , 26730..26759 , 26760..26789 , 26790..26819 , 26820..26849 , 26850..26879 , 26880..26909 , 26910..26939 , 26940..26969 , 26970..26999 , 27000..27029 , 27030..27059 , 27060..27089 , 27090..27119 , 27120..27149 , 27150..27179 , 27180..27209 , 27210..27239 , 27240..27269 , 27270..27299 , 27300..27329 , 27330..27359 , 27360..27389 , 27390..27419 , 27420..27449 , 27450..27479 , 27480..27509 , 27510..27539 , 27540..27569 , 27570..27599 , 27600..27629 , 27630..27659 , 27660..27689 , 27690..27719 , 27720..27749 , 27750..27779 , 27780..27809 , 27810..27839 , 27840..27869 , 27870..27899 , 27900..27929 , 27930..27959 , 27960..27989 , 27990..28019 , 28020..28049 , 28050..28079 , 28080..28109 , 28110..28139 , 28140..28169 , 28170..28199 , 28200..28229 , 28230..28259 , 28260..28289 , 28290..28319 , 28320..28349 , 28350..28379 , 28380..28409 , 28410..28439 , 28440..28469 , 28470..28499 , 28500..28529 , 28530..28559 , 28560..28589 , 28590..28619 , 28620..28649 , 28650..28679 , 28680..28709 , 28710..28739 , 28740..28769 , 28770..28799 , 28800..28829 , 28830..28859 , 28860..28889 , 28890..28919 , 28920..28949 , 28950..28979 , 28980..29009 , 29010..29039 , 29040..29069 , 29070..29099 , 29100..29129 , 29130..29159 , 29160..29189 , 29190..29219 , 29220..29249 , 29250..29279 , 29280..29309 , 29310..29339 , 29340..29369 , 29370..29399 , 29400..29429 , 29430..29459 , 29460..29489 , 29490..29519 , 29520..29549 , 29550..29579 , 29580..29609 , 29610..29639 , 29640..29669 , 29670..29699 , 29700..29729 , 29730..29759 , 29760..29789 , 29790..29819 , 29820..29849 , 29850..29879 , 29880..29909 , 29910..29939 , 29940..29969 , 29970..29999 , 30000..30029 , 30030..30059 , 30060..30089 , 30090..30119 , 30120..30149 , 30150..30179 , 30180..30209 , 30210..30239 , 30240..30269 , 30270..30299 , 30300..30329 , 30330..30359 , 30360..30389 , 30390..30419 , 30420..30449 , 30450..30479 , 30480..30509 , 30510..30539 , 30540..30569 , 30570..30599 , 30600..30629 , 30630..30659 , 30660..30689 , 30690..30719 , 30720..30749 , 30750..30779 , 30780..30809 , 30810..30839 , 30840..30869 , 30870..30899 , 30900..30929 , 30930..30959 , 30960..30989, >>Next

Sequences-and-series/282814: Choose the explicit formula for the sequence 1, 1/4, 1/9, 1/16, ... Then find a15.
(15 is below a. Not sure how to type that here, so I posted a pic of the question and answers here: http://i44.tinypic.com/16lwyzn.jpg)
1 solutions

Answer 205308 by Alan3354(30993) About Me  on 2010-03-19 10:07:58 (Show Source):
You can put this solution on YOUR website!
The most likely and simple series that fits is 1/a^2
a15 = 1/225


Travel_Word_Problems/282771: At an average rate of 55 km h how long will it take to drive225 km to the nearest tenth of an hour?
1 solutions

Answer 205299 by Alan3354(30993) About Me  on 2010-03-19 08:52:09 (Show Source):
You can put this solution on YOUR website!
There are only 2 numbers to work with.
What's your guess?


Geometry_Word_Problems/282783: A circle of diameter 6 in. has its center at the center of a square of side 6 in. Find the area of the region that is inside the square and outside the circle.
a. (36π - 36) in.2 b. (36 - 6π) in.2 c. (36 - 9π) in.2 d. (9π - 36) in.2 e. None of these
1 solutions

Answer 205292 by Alan3354(30993) About Me  on 2010-03-19 08:07:15 (Show Source):
You can put this solution on YOUR website!
A circle of diameter 6 in. has its center at the center of a square of side 6 in. Find the area of the region that is inside the square and outside the circle.
-----------------
It's the area of the square ( = 6*6)
minus the area of the circle = pi%2A3%5E2


logarithm/282787: Rewrite the following as an equivalent exponential equation. Do not solve
log(e) 0.989 = -0.0111
1 solutions

Answer 205290 by Alan3354(30993) About Me  on 2010-03-19 08:04:03 (Show Source):
You can put this solution on YOUR website!
log(e) 0.989 = -0.0111
ln(0.989) = -0.0111
e%5E-0.0111+=+0.989
There's nothing to solve


Geometry_Word_Problems/282764: If the height of a right circular cylinder is tripled and the diameter is halved, then the ratio of the new volume to the original volume is:
(A)4/3 (B) 3/4 (C) 3/2 (D) 2/3 (E) none of these

1 solutions

Answer 205286 by Alan3354(30993) About Me  on 2010-03-19 06:47:12 (Show Source):


Triangles/282674: The sides of a triangle measure 9, 15, and 18. If the shortest side of a similar triangle measures 6, find the length of the longest side of this triangle.
1 solutions

Answer 205222 by Alan3354(30993) About Me  on 2010-03-18 20:39:31 (Show Source):
You can put this solution on YOUR website!
9:18::6:s
9s=108
s = 12


Quadratic_Equations/282670: 2x^2+2x+3=0 can you help me solve this

1 solutions

Answer 205221 by Alan3354(30993) About Me  on 2010-03-18 20:37:50 (Show Source):
You can put this solution on YOUR website!
2x^2+2x+3=0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 2x%5E2%2B2x%2B3+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%282%29%5E2-4%2A2%2A3=-20.

The discriminant -20 is less than zero. That means that there are no solutions among real numbers.

If you are a student of advanced school algebra and are aware about imaginary numbers, read on.


In the field of imaginary numbers, the square root of -20 is + or - sqrt%28+20%29+=+4.47213595499958.

The solution is , or
Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B2%2Ax%2B3+%29




Trigonometry-basics/282651: Can I please have help with verifying the identity.
sec(x)-1/sec(x)=sin(x)tan(x)

Thank you so much
1 solutions

Answer 205213 by Alan3354(30993) About Me  on 2010-03-18 20:19:32 (Show Source):
You can put this solution on YOUR website!
sec(x)-1/sec(x)=sin(x)tan(x)
-------------------
Multiply thru by cos(x)


Trigonometry-basics/282656: Can you please help me verify the identity.
(sinx-cosx/sinx)+(cosx-sinx/cosx)=2-secx cscx
Thank you so much
1 solutions

Answer 205212 by Alan3354(30993) About Me  on 2010-03-18 20:16:28 (Show Source):
You can put this solution on YOUR website!
(sinx-cosx/sinx)+(cosx-sinx/cosx)=2-secx cscx
Multiply thru by sin*cos
sincos - cos^2 + cos*sin - sin^2 = 2sincos - 1
2sincos - (sin^2 + cos^2) = 2sincos - 1
-1 = -1


Quadratic_Equations/282614: Hi I have a question what is these equations:y=x^2+3, y=-x^2-4x-4, y=x^2+2x+3
Thank You
1 solutions

Answer 205200 by Alan3354(30993) About Me  on 2010-03-18 19:17:34 (Show Source):
You can put this solution on YOUR website!
They are parabolas.


Linear-systems/282515: How do you solve 2y=6x+4?
1 solutions

Answer 205108 by Alan3354(30993) About Me  on 2010-03-18 15:53:20 (Show Source):
You can put this solution on YOUR website!
How do you solve 2y=6x+4?
There's no unique solution.
You can pick any value for x and find a value for y, an infinite # of combinatiions.
-------------
If you graph it, it's a straight line, and every point on the line is a "solution."


Linear_Algebra/282514: x+y=1 x-y=1 linear equation problwn [ i could nt find anything else ]
1 solutions

Answer 205104 by Alan3354(30993) About Me  on 2010-03-18 15:48:12 (Show Source):
You can put this solution on YOUR website!
x+y=1
x-y=1
------ Add
2x = 2
x = 1
-------
y = 0


Polynomials-and-rational-expressions/282389: use 5 step problem solving. The product of two facing pages is 420. Find the page numbers
1 solutions

Answer 205102 by Alan3354(30993) About Me  on 2010-03-18 15:46:01 (Show Source):
You can put this solution on YOUR website!
sqrt%28420%29 = 20.49.....
--> 20 & 21


Miscellaneous_Word_Problems/282506: FInd two fractions that have the same produc and difference. Neither the numerator nor denominator can equal 0. What would the fractions be? 1/1 and 1/1? I'm not really sure.
1 solutions

Answer 205099 by Alan3354(30993) About Me  on 2010-03-18 15:39:02 (Show Source):
You can put this solution on YOUR website!
FInd two fractions that have the same produc and difference. Neither the numerator nor denominator can equal 0. What would the fractions be? 1/1 and 1/1?
-------------
1/ab = (1/a) - (1/b)
1/ab = (b-a)/ab
b-a = 1
b = a+1
-----------
Any pair where the denominators are consecutive integers.
eg 1/3 and 1/4
1/16 and 1/17
etc


Probability-and-statistics/282486: You have seven cards. One is picked without looking what is the probability?

1 solutions

Answer 205094 by Alan3354(30993) About Me  on 2010-03-18 15:11:07 (Show Source):
You can put this solution on YOUR website!
the probability of what?


Equations/282483: Help...
A sailboat travels 20 miles downstream in 4 hours. It returns in 5 hours. Find the speed of the sailboat in still water and the rate of the current.
Ugggg
Thanks
1 solutions

Answer 205093 by Alan3354(30993) About Me  on 2010-03-18 14:58:52 (Show Source):
You can put this solution on YOUR website!
A sailboat travels 20 miles downstream in 4 hours. It returns in 5 hours. Find the speed of the sailboat in still water and the rate of the current
--------------------
Write down what you know:
b = speed of the boat
c = speed of the current
Downstream the speed is b+c
Upstream it's b-c
The distance is the same
---------------------------
d = rt
20 = 4*(b+c) = 5*(b-c)
-----------------------
4b + 4c = 20
5b - 5c = 20
------------
b + c = 5
b - c = 4
------------ Add
2b = 9
b = 4.5 mph
------------
c = 1/2 mph


Points-lines-and-rays/282484: In a right angle triangle, line AB=30 and line BC=24. What is the value of line line AC? I have tried the Pythagorean theoroem.
1 solutions

Answer 205092 by Alan3354(30993) About Me  on 2010-03-18 14:51:49 (Show Source):
You can put this solution on YOUR website!
In a right angle triangle, line AB=30 and line BC=24. What is the value of line line AC?
------------
If AB is the hypotenuse, then
b%5E2+=+30%5E2+-+24%5E2
b%5E2+=+900+-+576
b%5E2+=+324
b = 18
------


Exponents-negative-and-fractional/282471: Can the answer to 25^(1/2) be 5 and -5?
1 solutions

Answer 205087 by Alan3354(30993) About Me  on 2010-03-18 14:20:57 (Show Source):
You can put this solution on YOUR website!
Yes.
5*5 = 25
(-5)*(-5) = 25
There are always 2 square roots, 3 cube roots, 4 4th roots, etc.
Square roots are plus and minus.


Polynomials-and-rational-expressions/282385: which one is correct?
10x%5E2%2A10x%5E7=10x%5E9
or
10x%5E2%2A10x%5E7=100x%5E9
1 solutions

Answer 205041 by Alan3354(30993) About Me  on 2010-03-18 10:15:56 (Show Source):
You can put this solution on YOUR website!
10x%5E2%2A10x%5E7+=+10%2A10%2Ax%5E2%2Ax%5E7
= 100x%5E9
----------------
if x = 2:
10x^2 = 40
10x^7 = 1280
40*1280 = 51200
----------------
100*2^9 = 51200
----------------
----------------
If x = 1:
10x^2 = 10
10x^7 = 10
10*10 = 100
-----------
100*1^9 = 100





decimal-numbers/282398: how do you do this problem? i just need an example and im on my way!
40% of 50=
thank you
1 solutions

Answer 205038 by Alan3354(30993) About Me  on 2010-03-18 10:07:09 (Show Source):
You can put this solution on YOUR website!
40% of 50=
-----------
per cent means "out of 100", 1 cent = 1/100 of a dollar, century = 100 years, etc
-----------
40% = 40/100 = 0.4
0.4*50 = 20


Numeric_Fractions/282396: I am trying to understand how to divide fractions.
can you help me with this problem?
2/4 divided by 1/5=
thank you
1 solutions

Answer 205034 by Alan3354(30993) About Me  on 2010-03-18 09:59:00 (Show Source):
You can put this solution on YOUR website!
2/4 divided by 1/5
-------------
Invert the divisor (1/5) and multiply
= (2/4)*(5/1)
= 10/4
= 5/2


Polynomials-and-rational-expressions/282391: what is the factorization of 9x^4 - 3x^2? I came up with the answer being..3x^2(x2 - 3). Just wanted to make sure this is right.
1 solutions

Answer 205033 by Alan3354(30993) About Me  on 2010-03-18 09:57:27 (Show Source):
You can put this solution on YOUR website!
what is the factorization of 9x^4 - 3x^2?
I came up with the answer being..3x^2(x2 - 3). Just wanted to make sure this is right.
----------
3x^2(x2 - 3) = 3x^4 - 9x^2, not the same
-------------
9x%5E4+-+3x%5E2+=+3x%5E2%283x%5E2+-+1%29


Quadratic-relations-and-conic-sections/282370: i must find the distance between two points. (-2,3) and (5,4). i must leave as simplified radical. i think the answer is 3/1. please help me if possible. thanks
1 solutions

Answer 205015 by Alan3354(30993) About Me  on 2010-03-18 09:06:29 (Show Source):
You can put this solution on YOUR website!
find the distance between two points. (-2,3) and (5,4). i must leave as simplified radical.
----------------
s+=+sqrt%28diffy%5E2+%2B+diffx%5E2%29
s+=+sqrt%281%5E2+%2B+7%5E2%29
s+=+sqrt%2850%29
s+=+5sqrt%282%29


Quadratic-relations-and-conic-sections/282376: what is an equation of the perpendicular bisector of the line between the points, (2,2) and (6,6). im not sure how to get this. please help me if possible thank you
1 solutions

Answer 205012 by Alan3354(30993) About Me  on 2010-03-18 08:56:41 (Show Source):
You can put this solution on YOUR website!
what is an equation of the perpendicular bisector of the line between the points, (2,2) and (6,6).
---------------
The slope of the line thru the points is 1 (6-2)/(6-2)
The midpoint is (4,4)
---------------
The slope of the line perpendicular is -1
Use y = mx+b to find the line thru (4,4) and m = -1
4 = -4 + b
b = 8
------
--> y = -x + 8
or x + y = 8


Quadratic-relations-and-conic-sections/282377: i am supposed to write an equation of a circle with the center at the origin and radius 6. i think it would be (x+0)^2/36 + (y+0)^2/36= 1. is this correct
1 solutions

Answer 205010 by Alan3354(30993) About Me  on 2010-03-18 08:53:19 (Show Source):
You can put this solution on YOUR website!
That's correct.
It simplifies to
x^2 + y^2 = 36


Polynomials-and-rational-expressions/282363: The officejet printer can copy Janet's dissertaion in 14 min. The laserjet printer can copy the same document in 8 min. IF the two machines work together how long would they take to copy the dissertation?
? minutes
1 solutions

Answer 205008 by Alan3354(30993) About Me  on 2010-03-18 08:51:12 (Show Source):
You can put this solution on YOUR website!
Use product/sum
--> 14*8/(14+8)
= 112/22
= 56/11
Same answer, less time finding it.


Quadratic-relations-and-conic-sections/282369: i must identify the conic. (x+2)^2/25 - (y-1)^2/9=1. i think its a hyperbola is this correct
1 solutions

Answer 205007 by Alan3354(30993) About Me  on 2010-03-18 08:49:19 (Show Source):
You can put this solution on YOUR website!
It's a hyperbola.
It's the difference of the squared terms --> hyperbola.
If they're added it's an ellipse.


Linear_Algebra/282372: solve the system of equations.
3x+4y+z=7
2y+z=3
-5x+3y+8z=-31 im not sure how to do this. i would greatly appreciate any help. thank you
1 solutions

Answer 205002 by Alan3354(30993) About Me  on 2010-03-18 08:24:14 (Show Source):
You can put this solution on YOUR website!
solve the system of equations.
3x+4y+z=7
2y+z=3
-5x+3y+8z=-31
-----------------
There's more than one way, but I'll use substitution since there's no x term in the 2nd eqn.
--------------
2y+z=3 --> z = 3-2y
Sub for z in the other 2 eqns
3x + 4y + (3-2y) = 7
-5x + 3y +8(3-2y) = -31
----------------
3x + 2y = 4
-5x -13y = -55
Now it's 2 eqn in 2 variables.
Multiply the 1st by 5 and the 2nd by 3
15x + 10y = 20
-15x -39y = -165
---------------- Add
-29y = -145
y = 5
-------
Sub for y in 3x + 2y = 4
--> x = -2
-------------
2y+z=3
--> z = -7
-------------
If you're gonna do a lot of these, use Excel and determinants.



Numeric_Fractions/282254: A phone company charges 15cents per call plus 8cents per minute. Find the cost of a 20 minute phone call.
1 solutions

Answer 204966 by Alan3354(30993) About Me  on 2010-03-17 22:49:43 (Show Source):
You can put this solution on YOUR website!
20*8 + 15
= 160 + 15
= $1.75


Equations/282172: kim started with $4 and saved $2 a week. write an equation the growth of her savings using X and Y as in #12.
1 solutions

Answer 204952 by Alan3354(30993) About Me  on 2010-03-17 21:25:41 (Show Source):
You can put this solution on YOUR website!
kim started with $4 and saved $2 a week. write an equation the growth of her savings using X and Y as in #12.
--------------------
savings = $4 + $2*t (t in weeks)
or y = 4 + 2x, y in $, x in weeks
-----------------
I don't have a #12


Polynomials-and-rational-expressions/282234: how do I solve this equation by factoring?
25x^2=36
1 solutions

Answer 204951 by Alan3354(30993) About Me  on 2010-03-17 21:21:54 (Show Source):
You can put this solution on YOUR website!
how do I solve this equation by factoring?
25x^2=36
-----------
25x%5E2+-+36+=+0
(5x - 6)*(5x + 6) = 0
x = 6/5
x = -6/5
----------
Factoring this is the long way:
25x^2=36
Take the sqrt of both sides
5x = ± 6
x = ± 6/5