{"id":2333,"date":"2025-05-20T20:39:33","date_gmt":"2025-05-20T17:39:33","guid":{"rendered":"https:\/\/cedra.academy\/?p=2333"},"modified":"2025-09-09T21:00:29","modified_gmt":"2025-09-09T18:00:29","slug":"rezolvarea-ecuatiilor-si-inecuatiilor-liniare-cu-o-necunoscuta-si-aplicarea-lor-in-probleme-practice","status":"publish","type":"post","link":"https:\/\/cedra.academy\/?p=2333","title":{"rendered":"Rezolvarea ecua\u021biilor \u0219i inecua\u021biilor liniare cu o necunoscut\u0103 \u0219i aplicarea lor \u00een probleme practice"},"content":{"rendered":"\n<div class=\"wp-block-file\"><a id=\"wp-block-file--media-d91245b8-8bd3-4e0b-a1aa-b3359abc181b\" href=\"https:\/\/cedra.academy\/wp-content\/uploads\/2025\/09\/Ecuatiile-si-inecuatiile.pptx\">Ecua\u021biile \u0219i inecua\u021biile liniare                           PPTX          .<\/a><a href=\"https:\/\/cedra.academy\/wp-content\/uploads\/2025\/09\/Ecuatiile-si-inecuatiile.pptx\" class=\"wp-block-file__button wp-element-button\" download aria-describedby=\"wp-block-file--media-d91245b8-8bd3-4e0b-a1aa-b3359abc181b\">Descarc\u0103<\/a><\/div>\n\n\n\n<p><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1. Ecua\u021biile liniare cu o necunoscut\u0103<\/h3>\n\n\n\n<p>O <strong>ecua\u021bie liniar\u0103 cu o necunoscut\u0103<\/strong> este o egalitate care con\u021bine o singur\u0103 variabil\u0103, notat\u0103 de obicei cu xxx, \u0219i poate fi scris\u0103 \u00een forma general\u0103: ax+b=0ax + b = 0ax+b=0<\/p>\n\n\n\n<p>unde aaa \u0219i bbb sunt numere reale, iar a\u22600a \\neq 0a\ue020=0.<\/p>\n\n\n\n<p><strong>Exemplu:<\/strong> 3x+5=03x + 5 = 03x+5=0<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">1.1. Metoda de rezolvare<\/h4>\n\n\n\n<p>Pentru a rezolva o ecua\u021bie liniar\u0103, urm\u0103m pa\u0219ii:<\/p>\n\n\n\n<ol>\n<li>Mut\u0103m termenii liberi pe cealalt\u0103 parte a egalit\u0103\u021bii:<\/li>\n<\/ol>\n\n\n\n<p>3x=\u221253x = -53x=\u22125<\/p>\n\n\n\n<ol start=\"2\">\n<li>\u00cemp\u0103r\u021bim ambele p\u0103r\u021bi la coeficientul necunoscutei:<\/li>\n<\/ol>\n\n\n\n<p>x=\u221253x = -\\frac{5}{3}x=\u221235\u200b<\/p>\n\n\n\n<p>Astfel, solu\u021bia ecua\u021biei este x=\u221253x = -\\frac{5}{3}x=\u221235\u200b.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">2. Inecua\u021biile liniare cu o necunoscut\u0103<\/h3>\n\n\n\n<p>O <strong>inecua\u021bie liniar\u0103 cu o necunoscut\u0103<\/strong> are forma: ax+b&gt;0sauax+b&lt;0sauax+b\u22650sauax+b\u22640ax + b &gt; 0 \\quad \\text{sau} \\quad ax + b &lt; 0 \\quad \\text{sau} \\quad ax + b \\ge 0 \\quad \\text{sau} \\quad ax + b \\le 0ax+b&gt;0sauax+b&lt;0sauax+b\u22650sauax+b\u22640<\/p>\n\n\n\n<p>unde a\u22600a \\neq 0a\ue020=0.<\/p>\n\n\n\n<p><strong>Exemplu:<\/strong> 2x\u22124&lt;02x &#8211; 4 &lt; 02x\u22124&lt;0<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">2.1. Metoda de rezolvare<\/h4>\n\n\n\n<p>Pa\u0219ii sunt similari cu cei pentru ecua\u021bii:<\/p>\n\n\n\n<ol>\n<li>Mut\u0103m termenul liber pe cealalt\u0103 parte:<\/li>\n<\/ol>\n\n\n\n<p>2x&lt;42x &lt; 42x&lt;4<\/p>\n\n\n\n<ol start=\"2\">\n<li>\u00cemp\u0103r\u021bim ambele p\u0103r\u021bi la coeficientul lui xxx (pozitiv sau negativ \u2013 dac\u0103 e negativ, schimb\u0103m sensul inegalit\u0103\u021bii):<\/li>\n<\/ol>\n\n\n\n<p>x&lt;2x &lt; 2x&lt;2<\/p>\n\n\n\n<p>Deci solu\u021bia este mul\u021bimea numerelor reale mai mici dec\u00e2t 2: x\u2208(\u2212\u221e,2)x \\in (-\\infty, 2)x\u2208(\u2212\u221e,2).<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">3. Aplicarea ecua\u021biilor \u0219i inecua\u021biilor \u00een probleme practice<\/h3>\n\n\n\n<p>Ecua\u021biile \u0219i inecua\u021biile liniare sunt instrumente esen\u021biale pentru rezolvarea problemelor din via\u021ba real\u0103, cum ar fi:<\/p>\n\n\n\n<ol>\n<li><strong>Probleme cu bani:<\/strong><br>Exemplu: \u201eMaria are cu 5 lei mai mult dec\u00e2t Ana. Dac\u0103 Ana are xxx lei, c\u00e2\u021bi bani are Maria?\u201d<br>Ecua\u021bia: x+5=yx + 5 = yx+5=y, unde yyy este suma Mariei.<\/li>\n\n\n\n<li><strong>Probleme de propor\u021bii \u0219i m\u0103sur\u0103tori:<\/strong><br>Exemplu: \u201eLungimea unui dreptunghi este cu 3 m mai mare dec\u00e2t l\u0103\u021bimea sa. Perimetrul dreptunghiului este 22 m. Care sunt dimensiunile dreptunghiului?\u201d<br>Ecua\u021bia: 2(l+L)=222(l + L) = 222(l+L)=22<br>Substituind L=l+3L = l + 3L=l+3, ob\u021binem:<\/li>\n<\/ol>\n\n\n\n<p>2(l+l+3)=22\u21d24l+6=22\u21d2l=4&nbsp;m,\u2009L=7&nbsp;m2(l + l + 3) = 22 \\Rightarrow 4l + 6 = 22 \\Rightarrow l = 4 \\text{ m}, \\, L = 7 \\text{ m}2(l+l+3)=22\u21d24l+6=22\u21d2l=4&nbsp;m,L=7&nbsp;m<\/p>\n\n\n\n<ol start=\"3\">\n<li><strong>Probleme cu inecua\u021bii (condi\u021bii limit\u0103):<\/strong><br>Exemplu: \u201eO fabric\u0103 poate produce cel mult 500 de produse pe zi. Dac\u0103 xxx este num\u0103rul produselor produse, care este condi\u021bia pentru xxx?\u201d<br>Inecuatia: x\u2264500x \\le 500x\u2264500<\/li>\n<\/ol>\n\n\n\n<p>Astfel, elevii pot folosi ecua\u021biile \u0219i inecua\u021biile pentru a g\u0103si solu\u021bii \u0219i pentru a verifica dac\u0103 anumite condi\u021bii sunt respectate \u00een situa\u021bii reale.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">4. Concluzii<\/h3>\n\n\n\n<ul>\n<li>Ecua\u021biile liniare cu o necunoscut\u0103 ne ajut\u0103 s\u0103 afl\u0103m valoarea unei variabile necunoscute.<\/li>\n\n\n\n<li>Inecua\u021biile liniare ne arat\u0103 condi\u021biile sub care anumite situa\u021bii sunt posibile.<\/li>\n\n\n\n<li>\u00cen via\u021ba real\u0103, aceste instrumente matematice se aplic\u0103 \u00een finan\u021be, m\u0103sur\u0103tori, planificarea produc\u021biei, programe de lucru \u0219i multe alte domenii.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" width=\"1024\" height=\"768\" src=\"https:\/\/cedra.academy\/wp-content\/uploads\/2025\/09\/Ecuatiile-si-inecuatiile.jpg\" alt=\"\" class=\"wp-image-2336\" style=\"aspect-ratio:1.3333333333333333;width:757px;height:auto\" srcset=\"https:\/\/cedra.academy\/wp-content\/uploads\/2025\/09\/Ecuatiile-si-inecuatiile.jpg 1024w, https:\/\/cedra.academy\/wp-content\/uploads\/2025\/09\/Ecuatiile-si-inecuatiile-300x225.jpg 300w, https:\/\/cedra.academy\/wp-content\/uploads\/2025\/09\/Ecuatiile-si-inecuatiile-768x576.jpg 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>1. Ecua\u021biile liniare cu o necunoscut\u0103 O ecua\u021bie liniar\u0103 cu o necunoscut\u0103 este o egalitate care con\u021bine o singur\u0103 variabil\u0103, notat\u0103 de obicei cu xxx, \u0219i poate fi scris\u0103 \u00een [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":2335,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13,10],"tags":[],"_links":{"self":[{"href":"https:\/\/cedra.academy\/index.php?rest_route=\/wp\/v2\/posts\/2333"}],"collection":[{"href":"https:\/\/cedra.academy\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cedra.academy\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cedra.academy\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/cedra.academy\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2333"}],"version-history":[{"count":3,"href":"https:\/\/cedra.academy\/index.php?rest_route=\/wp\/v2\/posts\/2333\/revisions"}],"predecessor-version":[{"id":2339,"href":"https:\/\/cedra.academy\/index.php?rest_route=\/wp\/v2\/posts\/2333\/revisions\/2339"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cedra.academy\/index.php?rest_route=\/wp\/v2\/media\/2335"}],"wp:attachment":[{"href":"https:\/\/cedra.academy\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2333"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cedra.academy\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2333"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cedra.academy\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2333"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}