{"id":377,"date":"2022-04-12T10:23:53","date_gmt":"2022-04-12T10:23:53","guid":{"rendered":"http:\/\/7thclass.deltapublications.in\/?page_id=377"},"modified":"2024-10-23T15:03:54","modified_gmt":"2024-10-23T15:03:54","slug":"r-9-find-missing-angles-in-triangles-and-quadrilaterals","status":"publish","type":"page","link":"https:\/\/7thclass.deltapublications.in\/index.php\/r-9-find-missing-angles-in-triangles-and-quadrilaterals\/","title":{"rendered":"R.9 Find missing angles in triangles and quadrilaterals"},"content":{"rendered":"\n<h2 class=\"wp-block-heading has-text-align-center has-text-color\" style=\"color:#00056d;text-transform:uppercase\"><strong> Find missing angles in triangles and quadrilaterals<\/strong><\/h2>\n\n\n\n<p class=\"has-text-color has-huge-font-size\" style=\"color:#74008b\"><strong>Key notes:<\/strong><\/p>\n\n\n\n<div class=\"wp-block-group has-large-font-size\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\">\n<p><strong>Triangles<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Sum of Angles Theorem:<\/strong> The sum of the interior angles in a triangle is always 180 degrees.<\/li>\n\n\n\n<li><strong>Equilateral Triangle:<\/strong> All three sides are equal, and all three angles are 60 degrees.<\/li>\n\n\n\n<li><strong>Isosceles Triangle:<\/strong> Two sides are equal, and the angles opposite those sides are equal.<\/li>\n\n\n\n<li><strong>Right Triangle:<\/strong> One angle is 90 degrees. The other two angles are complementary (their sum is 90 degrees).<\/li>\n<\/ul>\n\n\n\n<p><strong>Quadrilaterals<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Sum of Angles Theorem:<\/strong> The sum of the interior angles in a quadrilateral is always 360 degrees.<\/li>\n\n\n\n<li><strong>Parallelogram:<\/strong> Opposite sides are parallel, and opposite angles are equal.<\/li>\n\n\n\n<li><strong>Rectangle:<\/strong> A parallelogram with four right angles.<\/li>\n\n\n\n<li><strong>Rhombus:<\/strong> A parallelogram with all four sides equal.<\/li>\n\n\n\n<li><strong>Square:<\/strong> A parallelogram with four right angles and all four sides equal.<\/li>\n\n\n\n<li><strong>Trapezoid:<\/strong> A quadrilateral with one pair of parallel sides.<\/li>\n<\/ul>\n\n\n\n<p><strong>Finding Missing Angles<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Use the appropriate theorem or property for the given figure.<\/strong><\/li>\n\n\n\n<li><strong>Set up an equation based on the sum of the angles.<\/strong><\/li>\n\n\n\n<li><strong>Solve the equation to find the missing angle.<\/strong><\/li>\n<\/ol>\n\n\n\n<p><strong>Examples:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Triangle:<\/strong> If two angles of a triangle are 40 degrees and 70 degrees, find the third angle.\n<ul class=\"wp-block-list\">\n<li>40 + 70 + x = 180<\/li>\n\n\n\n<li>x = 70 degrees<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Quadrilateral:<\/strong> If three angles of a quadrilateral are 100 degrees, 120 degrees, and 80 degrees, find the fourth angle.\n<ul class=\"wp-block-list\">\n<li>100 + 120 + 80 + x = 360<\/li>\n\n\n\n<li>x = 60 degrees<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-group has-large-font-size\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\">\n<p class=\"has-text-align-center has-text-color has-large-font-size\" style=\"color:#105000\"><strong>Learn with an example<\/strong><\/p>\n\n\n\n<div class=\"wp-block-group has-primary-color has-text-color has-background\" style=\"background-color:#e1e1fe\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group has-background-background-color has-background\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"has-text-color\" style=\"color:#b00012\">\ud83c\udf00 <strong>What is the measure of the missing angle?<\/strong><\/p>\n\n\n<div class=\"wp-block-image is-resized\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-6-2.png\" alt=\"\" class=\"wp-image-4829\" srcset=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-6-2.png 500w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-6-2-300x300.png 300w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-6-2-150x150.png 150w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-6-2-400x400.png 400w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/figure><\/div>\n\n\n<p>______\u00b0<\/p>\n<\/div><\/div>\n\n\n\n<p>The sum of the three angles must be 180\u00b0. The two angles you know measure 90\u00b0 and 30\u00b0.<\/p>\n\n\n\n<p>Write an equation and find the measure of the unknown angle.<\/p>\n\n\n\n<p>90\u00b0 + 30\u00b0 + ? = 180\u00b0<\/p>\n\n\n\n<p>120\u00b0 + ? = 180\u00b0<\/p>\n\n\n\n<p>? = 180\u00b0 \u2212 120\u00b0<\/p>\n\n\n\n<p>? = 60\u00b0<\/p>\n\n\n\n<p>The measure of the missing angle is 60\u00b0.<\/p>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-group has-primary-color has-text-color has-background\" style=\"background-color:#c8f8d3\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group has-background-background-color has-background\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"has-text-color\" style=\"color:#b00012\">\ud83c\udf00 <strong>What is the measure of the missing angle?<\/strong><\/p>\n\n\n\n<p>____ \u00b0<\/p>\n\n\n<div class=\"wp-block-image is-resized\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-7-2.png\" alt=\"\" class=\"wp-image-4830\" srcset=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-7-2.png 500w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-7-2-300x300.png 300w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-7-2-150x150.png 150w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/01\/Untitled-design-7-2-400x400.png 400w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/figure><\/div><\/div><\/div>\n\n\n\n<p>The sum of the three angles must be 180\u00b0. The two angles you know measure 59\u00b0 and 31\u00b0.<\/p>\n\n\n\n<p>Write an equation and find the measure of the unknown angle.<\/p>\n\n\n\n<p>59\u00b0 + 31\u00b0 + ? = 180\u00b0<\/p>\n\n\n\n<p>90\u00b0 + ? = 180\u00b0<\/p>\n\n\n\n<p>? = 180\u00b0 \u2212 90\u00b0<\/p>\n\n\n\n<p>? = 90\u00b0<\/p>\n\n\n\n<p>The measure of the missing angle is 90\u00b0.<\/p>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-group has-primary-color has-text-color has-background\" style=\"background-color:#f8cdcd\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group has-primary-color has-background-background-color has-text-color has-background\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"has-text-color\" style=\"color:#b00012\">\ud83c\udf00 <strong>What is the measure of the missing angle?<\/strong><\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"316\" height=\"218\" src=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2024\/10\/image-15.png\" alt=\"\" class=\"wp-image-14464\" style=\"aspect-ratio:1.4495412844036697;width:442px;height:auto\" srcset=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2024\/10\/image-15.png 316w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2024\/10\/image-15-300x207.png 300w\" sizes=\"auto, (max-width: 316px) 100vw, 316px\" \/><\/figure><\/div>\n\n\n<p>_____ \u00b0<\/p>\n<\/div><\/div>\n\n\n\n<p>The sum of the four angles must be 360\u00b0. The three angles you know measure 49\u00b0, 66\u00b0, and 146\u00b0.<\/p>\n\n\n\n<p>Write an equation and find the measure of the unknown angle.<\/p>\n\n\n\n<p>49\u00b0 + 66\u00b0 + 146\u00b0 + ? = 360\u00b0<\/p>\n\n\n\n<p>261\u00b0 + ? = 360\u00b0<\/p>\n\n\n\n<p>? = 360\u00b0 \u2212 261\u00b0<\/p>\n\n\n\n<p>? = 99\u00b0<\/p>\n\n\n\n<p>The measure of the missing angle is 99\u00b0.<\/p>\n<\/div><\/div>\n\n\n\n<p class=\"has-text-color has-large-font-size\" style=\"color:#d90000\"><strong>Let&#8217;s practice!\ud83d\udd8a\ufe0f<\/strong><\/p>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-92.png\" alt=\"\" class=\"wp-image-6764\" srcset=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-92.png 500w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-92-300x300.png 300w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-92-150x150.png 150w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-92-400x400.png 400w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/wordwall.net\/play\/79931\/274\/303\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-93.png\" alt=\"\" class=\"wp-image-6766\" srcset=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-93.png 500w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-93-300x300.png 300w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-93-150x150.png 150w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-93-400x400.png 400w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/a><\/figure>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Find missing angles in triangles and quadrilaterals Key notes: Triangles Quadrilaterals Finding Missing Angles Examples: Learn with an example \ud83c\udf00 What is the measure of the missing angle? ______\u00b0 The sum of the three angles must be 180\u00b0. The two angles you know measure 90\u00b0 and 30\u00b0. Write an equation and find the measure of<a class=\"more-link\" href=\"https:\/\/7thclass.deltapublications.in\/index.php\/r-9-find-missing-angles-in-triangles-and-quadrilaterals\/\">Continue reading <span class=\"screen-reader-text\">&#8220;R.9 Find missing angles in triangles and quadrilaterals&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"om_disable_all_campaigns":false,"footnotes":""},"class_list":["post-377","page","type-page","status-publish","hentry","entry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/377","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/comments?post=377"}],"version-history":[{"count":15,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/377\/revisions"}],"predecessor-version":[{"id":14546,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/377\/revisions\/14546"}],"wp:attachment":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/media?parent=377"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}