{"id":34252,"date":"2016-08-23T07:08:07","date_gmt":"2016-08-23T14:08:07","guid":{"rendered":"https:\/\/gmatclub.com\/blog\/2016\/08\/land-your-score-geometry-problem-shortcuts\/"},"modified":"2016-08-23T07:08:07","modified_gmt":"2016-08-23T14:08:07","slug":"land-your-score-geometry-problem-shortcuts","status":"publish","type":"post","link":"https:\/\/gmatclub.com\/blog\/land-your-score-geometry-problem-shortcuts\/","title":{"rendered":"Land Your Score: Geometry Problem Shortcuts"},"content":{"rendered":"<div><img decoding=\"async\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/iStock_7140634_SMALL.jpg\" class=\"featured-image\" \/><\/p>\n<div><\/div>\n<\/div>\n<p><span><a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/iStock_7140634_SMALL.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6634\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/iStock_7140634_SMALL.jpg\" alt=\"geometry formula\" width=\"800\" height=\"600\" \/><\/a><\/span><\/p>\n<p><span>GMAT geometry problems tend to be one of the scariest of the Quantitative topic areas. Fortunately, all the geometry you need to remember could fit in the palm of your hand. Since you can\u2019t actually put it in your palm on Test Day, here are some tricks for tackling GMAT geometry without notes.<\/span><\/p>\n<h2><span>Geometry problems with lines and angles<\/span><\/h2>\n<p><strong><strong>\u00a0<a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/geom1.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6606\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/geom1.jpg\" alt=\"geom1\" width=\"175\" height=\"93\" \/><\/a><\/strong><\/strong><\/p>\n<p><span>If you are given a figure such as this, with no angle measures provided, all you would know is that certain pairs of angles sum to <strong>180<\/strong><\/span><strong>\u00b0<\/strong><span> and the sum of all four angles is <strong>360<\/strong><\/span><strong>\u00b0<\/strong><span>.<\/span><\/p>\n<p><span>There is no way to determine the measures of individual angles, <\/span><b>so answer choices other than 180<\/b><b>\u00b0<\/b><b> or 360<\/b><b>\u00b0<\/b><b> will not be correct<\/b><span>.<\/span><\/p>\n<h2><span>Finding the area of triangles<\/span><\/h2>\n<p><span>The formula for the area of a <\/span><b>triangle<\/b><span> is <a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.18.13-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone  wp-image-6619\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.18.13-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.18.13 PM\" width=\"96\" height=\"25\" \/><\/a><\/span><\/p>\n<p><span>A triangle\u2019s base and height must be\u00a0perpendicular (meeting at a 90-degree angle). Right triangles are the only type of triangle that have side lengths as base and height. For all other triangles, consider one side the base and then draw in a line for the height.<\/span><\/p>\n<p><strong><strong>\u00a0<a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/geom2.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6607\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/geom2.jpg\" alt=\"geom2\" width=\"273\" height=\"94\" \/><\/a><\/strong><\/strong><\/p>\n<p><b>Equilateral<\/b><span> triangles have equal side lengths and angle measures; because all triangles have an internal angle sum of <strong>180\u00b0<\/strong>, each angle in an equilateral triangle is <strong>60\u00b0<\/strong>.<\/span><\/p>\n<p><b>Isosceles<\/b><span> triangles have two equal sides, and they also have two equal angles. Any time the GMAT presents a triangle with one vertex at the center of a circle, the triangle will be isosceles as each side will be the radius of the circle.<\/span><\/p>\n<p><a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/geom3.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6608\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/geom3.jpg\" alt=\"geom3\" width=\"144\" height=\"137\" \/><\/a><\/p>\n<h2><span>Quadrilateral figures<\/span><\/h2>\n<p><span>The formula for the area of a <\/span><b>quadrilateral<\/b><span> (four-sided figure) is <\/span><em><span>(base)(height)<\/span><span>. <\/span><\/em><\/p>\n<p><span>Base and height must also be perpendicular for polygons other than triangles. In a rectangle, all angles are <strong>90\u00b0<\/strong>, but in a <\/span><b>parallelogram<\/b><span> (a figure with two pairs of parallel sides) that is not a rectangle, you must draw the height just like with a triangle.<\/span><\/p>\n<p><a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/geom4.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6609\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/geom4.jpg\" alt=\"geom4\" width=\"240\" height=\"118\" \/><\/a><\/p>\n<p>Rectangles and squares are types of parallelograms, ones where all the angles are equal.<\/p>\n<h2><span>Formulas for circles<\/span><\/h2>\n<p><span>The formula for the area of a <\/span><b>circle<\/b><span> is <\/span><span>\u00a0and the formula for the <\/span><b>circumference<\/b><span> is <a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.18.39-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6621\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.18.39-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.18.39 PM\" width=\"70\" height=\"20\" \/><\/a>.<\/span><\/p>\n<p><span>Some people have trouble keeping the two important equations straight when they encounter a circle geometry problem on the GMAT, so I\u2019ll share with you a mnemonic my Kaplan colleague Gene Suhir shares with students:<\/span><\/p>\n<p><span><a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.02.24-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6613\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.02.24-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.02.24 PM\" width=\"230\" height=\"34\" \/><\/a><\/span><\/p>\n<p><span>\u00a0\u00a0<a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.02.31-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6614\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.02.31-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.02.31 PM\" width=\"202\" height=\"30\" \/><\/a><\/span><\/p>\n<p><span>Gene says you have to raise your voice an octave or so when you say \u201ctoo\u201d at the end, to remember that the 2 is an exponent. Give it a try.<\/span><\/p>\n<p><span>For more tips about circles, check out <\/span><a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/2016\/07\/06\/circle-ratio-geometry-problems\" target=\"_blank\"><span>my earlier post about circle ratios<\/span><\/a><span>.<\/span><\/p>\n<h2><span>Finding the volume of a solid<\/span><\/h2>\n<p><span>The formula for the <\/span><b>volume<\/b><span> of a <\/span><b>rectangular solid<\/b><span>, such as a cube, is <\/span><span>\u00a0For a <\/span><b>cylinder<\/b><span>, it\u2019s\u00a0<a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.19.03-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6622\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.19.03-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.19.03 PM\" width=\"36\" height=\"19\" \/><\/a><\/span><\/p>\n<p><span>Instead of memorizing those formulas, all you really need to do is remember this one: for any solid on the GMAT,\u00a0<\/span><em><span>v=(area of base)<\/span><span>(height)<\/span><\/em><span>. The base of a rectangular solid is a rectangle, and the area can be found using <a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.44.12-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6631\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.44.12-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.44.12 PM\" width=\"61\" height=\"19\" \/><\/a><\/span><span>\u00a0Multiply that by the height and you have <a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.44.19-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6632\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.44.19-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.44.19 PM\" width=\"84\" height=\"20\" \/><\/a><\/span><\/p>\n<p><span>For a cylinder, the base is a circle with area <a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.19.15-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6623\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.19.15-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.19.15 PM\" width=\"46\" height=\"17\" \/><\/a><\/span><span>. To find the volume, multiply that area times the height, or <a href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.19.27-PM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6624\" src=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/wp-content\/uploads\/sites\/15\/2016\/08\/Screen-Shot-2016-08-22-at-4.19.27-PM.png\" alt=\"Screen Shot 2016-08-22 at 4.19.27 PM\" width=\"56\" height=\"17\" \/><\/a><\/span><span>\u00a0Using your critical thinking skills while reviewing content during your prep can be as important as using it while answering questions! <\/span><\/p>\n<h2><span>Coordinate geometry problems<\/span><\/h2>\n<p>Every line on a coordinate system can be expressed in the form\u00a0<strong><em>y<\/em> =\u00a0<em>mx<\/em> +\u00a0<em>b<\/em><\/strong> where\u00a0<em>m<\/em> is the <strong>slope<\/strong> and\u00a0<em>b<\/em> is the <strong><em>y<\/em>-intercept<\/strong> (that is, the point where the line crosses the\u00a0<em>x<\/em> axis).<\/p>\n<p><span>Be sure you are comfortable with the relationships between parallel and perpendicular lines in the coordinate plane. Lines that are <\/span><b>parallel <\/b><span>have the same slope; they continue at the same slope to infinity and never cross. A line that is <\/span><b>perpendicular <\/b><span>to another line has a slope that is the <strong>negative<\/strong><\/span><b>\u00a0reciprocal<\/b><span> (change the sign and flip the fraction) of the other line\u2019s slope.<\/span><\/p>\n<p><span>For example, <\/span><strong><em>y\u00a0<\/em>=\u00a023<em>x\u00a0<\/em>+ 4<\/strong><span> will be parallel to all other lines that share a slope of <\/span><span>2<\/span><span>3<\/span><span>. A line that is perpendicular to <\/span><strong><em>y\u00a0<\/em>=\u00a023<em>x\u00a0<\/em>+ 4<\/strong><span> would have a slope of \u00a0<strong>-(1\/23)<\/strong><\/span><span>, which you find by changing the positive sign to a negative and taking the reciprocal of the fraction.<\/span><\/p>\n<p><span>Look for more GMAT strategies coming soon.<\/span><\/p>\n<p><i><span>Want to perfect your approach to geometry problems on Test Day? Give your Quant skills an intensive workout with our <\/span><\/i><a href=\"https:\/\/www.kaptest.com\/pages\/free-bootcamp?test=GMAT?utm_source=businessschoolinsider&amp;utm_medium=kaplan-blog&amp;utm_term=pre-business&amp;utm_content=blog-article&amp;utm_campaign=grad-gmat-bootcamp\" target=\"_blank\"><i><span>free GMAT bootcamp<\/span><\/i><\/a><i><span>.<\/span><\/i><\/p>\n<p>The post <a rel=\"nofollow\" href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\/2016\/08\/23\/geometry-problem-shortcuts\/\">Land Your Score: Geometry Problem Shortcuts<\/a> appeared first on <a rel=\"nofollow\" href=\"https:\/\/www.kaptest.com\/blog\/business-school-insider\">Business School Insider<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>GMAT geometry problems tend to be one of the scariest of the Quantitative topic areas. Fortunately, all the geometry you need to remember could fit in the palm of your&#8230;<\/p>\n","protected":false},"author":120,"featured_media":0,"comment_status":"open","ping_status":"1","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,558,243,940],"tags":[],"class_list":["post-34252","post","type-post","status-publish","format-standard","hentry","category-gmat","category-kaplan-blog","category-blog","category-gmat-prep-gmat","entry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/posts\/34252","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/users\/120"}],"replies":[{"embeddable":true,"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/comments?post=34252"}],"version-history":[{"count":0,"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/posts\/34252\/revisions"}],"wp:attachment":[{"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/media?parent=34252"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/categories?post=34252"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gmatclub.com\/blog\/wp-json\/wp\/v2\/tags?post=34252"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}