{"id":133,"date":"2026-01-12T15:50:05","date_gmt":"2026-01-12T15:50:05","guid":{"rendered":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/?post_type=chapter&#038;p=133"},"modified":"2026-01-12T15:50:05","modified_gmt":"2026-01-12T15:50:05","slug":"exponential-and-logarithmic-equations-and-models-get-stronger-answer-key","status":"publish","type":"chapter","link":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/chapter\/exponential-and-logarithmic-equations-and-models-get-stronger-answer-key\/","title":{"raw":"Exponential and Logarithmic Equations and Models: Get Stronger Answer Key","rendered":"Exponential and Logarithmic Equations and Models: Get Stronger Answer Key"},"content":{"raw":"<h2>Logarithmic Properties<\/h2>\r\n<ol>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\log_b(2)+\\log_b(7)+\\log_b(x)+\\log_b(y)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\log_b(13)-\\log_b(17)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]-k\\ln(4)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\ln(7xy)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\log_b(4)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\log_b(7)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]15\\log(x)+13\\log(y)-19\\log(z)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\dfrac{3}{2}\\log(x)-2\\log(y)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\dfrac{8}{3}\\log(x)+\\dfrac{14}{3}\\log(y)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\ln(2x^7)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\log(\\dfrac{xz^3}{\\sqrt{y}})[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\log_7(15)=\\dfrac{\\ln(15)}{\\ln(7)}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\log_{11}(5)=\\dfrac{\\log_5(5)}{\\log_5(11)}=\\dfrac{1}{b}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]\\log_{11}(\\dfrac{6}{11})=\\dfrac{\\log_5(\\dfrac{6}{11})}{\\log_5(11)}=\\dfrac{\\log_5(6)-\\log_5(11)}{\\log_5(11)}=\\dfrac{a-b}{b}=\\dfrac{a}{b}-1[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]3[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]2.81359[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]0.93913[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]-2.23266[\/latex]<\/li>\r\n<\/ol>\r\n<h2>Exponential and Logarithmic Equations and Models<\/h2>\r\n<ol>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=-\\dfrac{1}{3}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]n=-1[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]b=\\dfrac{6}{5}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=10[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">No solution<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]p=\\log(\\dfrac{17}{8})-7[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]k=-\\dfrac{\\ln(38)}{3}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=\\dfrac{\\ln(\\dfrac{38}{3})-8}{9}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=\\ln(12)[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]10^{-2}=\\dfrac{1}{100}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]n=49[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]k=\\dfrac{1}{36}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=\\dfrac{9-e}{8}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]n=1[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">No solution<\/li>\r\n \t<li class=\"whitespace-normal break-words\">No solution<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=\\pm\\dfrac{10}{3}[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=10[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=0[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]x=\\dfrac{3}{4}[\/latex]<\/li>\r\n<\/ol>\r\n<h2>Exponential and Logarithmic Models<\/h2>\r\n<ol>\r\n \t<li class=\"whitespace-normal break-words\">[latex]f(0)\\approx 16.7[\/latex]; The amount initially present is about [latex]16.7[\/latex] units.<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]150[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">exponential; [latex]f(x)=1.2^x[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">logarithmic\r\n<img class=\"alignnone size-full wp-image-5864\" src=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/42\/2024\/10\/29183355\/f2c565eac9430b9a10583283fca6fefedb2e55b9.jpg\" alt=\"Scatter plot of points representing a function f(x) with values increasing from x=1 to x=10. The points form an upward trend, with f(x) ranging from approximately 1 to 9. The graph includes labeled axes.\" width=\"377\" height=\"383\" \/><\/li>\r\n \t<li>logarithmic\r\n<img class=\"alignnone size-full wp-image-5865\" src=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/42\/2024\/10\/29183428\/f56273a501cbf3150c34abca2b51cf4df9734f8c.jpg\" alt=\"Scatter plot of points showing an upward trend with values on the y-axis increasing from approximately 9 to 13 as x progresses from 4 to 13. The points are closely spaced, indicating a steady increase, and the graph includes labeled axes.\" width=\"379\" height=\"566\" \/><\/li>\r\n \t<li><img class=\"alignnone size-full wp-image-5866\" src=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/42\/2024\/10\/29183501\/cc89a2c66cb6479f0f7f65b1229ba96f41b323c1.jpg\" alt=\"Graph of P(t)=1000\/(1+9e^(-0.6t))\" width=\"365\" height=\"409\" \/><\/li>\r\n \t<li>about [latex]1.4[\/latex] years<\/li>\r\n \t<li>about [latex]7.3[\/latex] years<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]A=125e^{(-0.3567t)}[\/latex]; [latex]A\\approx 43[\/latex] mg<\/li>\r\n \t<li class=\"whitespace-normal break-words\">about [latex]60[\/latex] days<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]A(t)=250e^{(-0.00822t)}[\/latex]; half-life: about [latex]84[\/latex] minutes<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]r\\approx -0.0667[\/latex], So the hourly decay rate is about [latex]6.67 \\%[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]f(t)=1350e^{(0.03466t)}[\/latex]; after [latex]3[\/latex] hours: [latex]P(180)\\approx 691,200[\/latex]<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]f(t)=256e^{(0.068110t)}[\/latex]; doubling time: about [latex]10[\/latex] minutes<\/li>\r\n \t<li class=\"whitespace-normal break-words\">about [latex]88[\/latex] minutes<\/li>\r\n \t<li class=\"whitespace-normal break-words\">[latex]T(t)=90e^{(-0.008377t)}+75[\/latex], where [latex]t[\/latex] is in minutes.<\/li>\r\n \t<li class=\"whitespace-normal break-words\">about [latex]113[\/latex] minutes<\/li>\r\n<\/ol>","rendered":"<h2>Logarithmic Properties<\/h2>\n<ol>\n<li class=\"whitespace-normal break-words\">[latex]\\log_b(2)+\\log_b(7)+\\log_b(x)+\\log_b(y)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\log_b(13)-\\log_b(17)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]-k\\ln(4)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\ln(7xy)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\log_b(4)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\log_b(7)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]15\\log(x)+13\\log(y)-19\\log(z)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\dfrac{3}{2}\\log(x)-2\\log(y)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\dfrac{8}{3}\\log(x)+\\dfrac{14}{3}\\log(y)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\ln(2x^7)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\log(\\dfrac{xz^3}{\\sqrt{y}})[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\log_7(15)=\\dfrac{\\ln(15)}{\\ln(7)}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\log_{11}(5)=\\dfrac{\\log_5(5)}{\\log_5(11)}=\\dfrac{1}{b}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]\\log_{11}(\\dfrac{6}{11})=\\dfrac{\\log_5(\\dfrac{6}{11})}{\\log_5(11)}=\\dfrac{\\log_5(6)-\\log_5(11)}{\\log_5(11)}=\\dfrac{a-b}{b}=\\dfrac{a}{b}-1[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]3[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]2.81359[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]0.93913[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]-2.23266[\/latex]<\/li>\n<\/ol>\n<h2>Exponential and Logarithmic Equations and Models<\/h2>\n<ol>\n<li class=\"whitespace-normal break-words\">[latex]x=-\\dfrac{1}{3}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]n=-1[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]b=\\dfrac{6}{5}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]x=10[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">No solution<\/li>\n<li class=\"whitespace-normal break-words\">[latex]p=\\log(\\dfrac{17}{8})-7[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]k=-\\dfrac{\\ln(38)}{3}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]x=\\dfrac{\\ln(\\dfrac{38}{3})-8}{9}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]x=\\ln(12)[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]10^{-2}=\\dfrac{1}{100}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]n=49[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]k=\\dfrac{1}{36}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]x=\\dfrac{9-e}{8}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]n=1[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">No solution<\/li>\n<li class=\"whitespace-normal break-words\">No solution<\/li>\n<li class=\"whitespace-normal break-words\">[latex]x=\\pm\\dfrac{10}{3}[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]x=10[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]x=0[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]x=\\dfrac{3}{4}[\/latex]<\/li>\n<\/ol>\n<h2>Exponential and Logarithmic Models<\/h2>\n<ol>\n<li class=\"whitespace-normal break-words\">[latex]f(0)\\approx 16.7[\/latex]; The amount initially present is about [latex]16.7[\/latex] units.<\/li>\n<li class=\"whitespace-normal break-words\">[latex]150[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">exponential; [latex]f(x)=1.2^x[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">logarithmic<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-5864\" src=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/42\/2024\/10\/29183355\/f2c565eac9430b9a10583283fca6fefedb2e55b9.jpg\" alt=\"Scatter plot of points representing a function f(x) with values increasing from x=1 to x=10. The points form an upward trend, with f(x) ranging from approximately 1 to 9. The graph includes labeled axes.\" width=\"377\" height=\"383\" \/><\/li>\n<li>logarithmic<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-5865\" src=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/42\/2024\/10\/29183428\/f56273a501cbf3150c34abca2b51cf4df9734f8c.jpg\" alt=\"Scatter plot of points showing an upward trend with values on the y-axis increasing from approximately 9 to 13 as x progresses from 4 to 13. The points are closely spaced, indicating a steady increase, and the graph includes labeled axes.\" width=\"379\" height=\"566\" \/><\/li>\n<li><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-5866\" src=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/42\/2024\/10\/29183501\/cc89a2c66cb6479f0f7f65b1229ba96f41b323c1.jpg\" alt=\"Graph of P(t)=1000\/(1+9e^(-0.6t))\" width=\"365\" height=\"409\" \/><\/li>\n<li>about [latex]1.4[\/latex] years<\/li>\n<li>about [latex]7.3[\/latex] years<\/li>\n<li class=\"whitespace-normal break-words\">[latex]A=125e^{(-0.3567t)}[\/latex]; [latex]A\\approx 43[\/latex] mg<\/li>\n<li class=\"whitespace-normal break-words\">about [latex]60[\/latex] days<\/li>\n<li class=\"whitespace-normal break-words\">[latex]A(t)=250e^{(-0.00822t)}[\/latex]; half-life: about [latex]84[\/latex] minutes<\/li>\n<li class=\"whitespace-normal break-words\">[latex]r\\approx -0.0667[\/latex], So the hourly decay rate is about [latex]6.67 \\%[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]f(t)=1350e^{(0.03466t)}[\/latex]; after [latex]3[\/latex] hours: [latex]P(180)\\approx 691,200[\/latex]<\/li>\n<li class=\"whitespace-normal break-words\">[latex]f(t)=256e^{(0.068110t)}[\/latex]; doubling time: about [latex]10[\/latex] minutes<\/li>\n<li class=\"whitespace-normal break-words\">about [latex]88[\/latex] minutes<\/li>\n<li class=\"whitespace-normal break-words\">[latex]T(t)=90e^{(-0.008377t)}+75[\/latex], where [latex]t[\/latex] is in minutes.<\/li>\n<li class=\"whitespace-normal break-words\">about [latex]113[\/latex] minutes<\/li>\n<\/ol>\n","protected":false},"author":15,"menu_order":12,"template":"","meta":{"_candela_citation":"[]","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"part":106,"module-header":"- Select Header -","content_attributions":[],"internal_book_links":[],"video_content":null,"cc_video_embed_content":{"cc_scripts":"","media_targets":[]},"try_it_collection":null,"_links":{"self":[{"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/pressbooks\/v2\/chapters\/133"}],"collection":[{"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/wp\/v2\/users\/15"}],"version-history":[{"count":1,"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/pressbooks\/v2\/chapters\/133\/revisions"}],"predecessor-version":[{"id":141,"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/pressbooks\/v2\/chapters\/133\/revisions\/141"}],"part":[{"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/pressbooks\/v2\/parts\/106"}],"metadata":[{"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/pressbooks\/v2\/chapters\/133\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/wp\/v2\/media?parent=133"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/pressbooks\/v2\/chapter-type?post=133"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/wp\/v2\/contributor?post=133"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/qrpracticepages\/wp-json\/wp\/v2\/license?post=133"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}