{"id":7448,"date":"2015-01-08T22:49:12","date_gmt":"2015-01-08T22:49:12","guid":{"rendered":"https:\/\/schooltutoring.com\/help\/?p=7448"},"modified":"2015-01-08T22:49:12","modified_gmt":"2015-01-08T22:49:12","slug":"math-review-of-factoring-trinomial-squares-and-differences-of-squares","status":"publish","type":"post","link":"https:\/\/schooltutoring.com\/help\/math-review-of-factoring-trinomial-squares-and-differences-of-squares\/","title":{"rendered":"Math Review of Factoring Trinomial Squares and Differences of Squares"},"content":{"rendered":"<h3>Overview<\/h3>\n<p>Trinomial squares are also known as perfect square trinomials, and are the squares of binomial expressions. They factor as (a + b)(a + b) or (a &#8211; b)(a &#8211; b) where a and b are real numbers. Forms such as (a + b)(a -b) are special products that are also called the difference of squares.<\/p>\n<h3>Trinomial Squares<\/h3>\n<p>When a squared binomial such as (a + b)(a + b) is multiplied using FOIL, the values of a and b follow a specific pattern. Recall that the first term is a<sup>2<\/sup>, the outside and inside terms are ab + ba, and the last term is b<sup>2<\/sup>. If a polynomial follows the form ax<sup>2<\/sup> + bx + c, a and c are perfect squares, and the b coefficient is twice the sum of ac, it is a perfect trinomial square. Suppose the polynomial is 36x<sup>2<\/sup> + 60x + 25. 36x<sup>2<\/sup> is a perfect square of 6x, and 25 is a perfect square of 5. The inner and outer terms are 30x + 30x or 60x. That polynomial is (6x + 5)<sup>2<\/sup>.<\/p>\n<p>Figure 1: The perfect square\u00a0trinomial follows a specific pattern.<\/p>\n<p style=\"text-align: center\"><a href=\"https:\/\/schooltutoring.com\/help\/wp-content\/uploads\/sites\/2\/2014\/09\/the-perfect-square-trinomial-pattern.png\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-6954 aligncenter\" src=\"https:\/\/schooltutoring.com\/help\/wp-content\/uploads\/sites\/2\/2014\/09\/the-perfect-square-trinomial-pattern.png\" width=\"300\" height=\"157\" \/><\/a><\/p>\n<h3>Negatives<\/h3>\n<p>What if the squared binomial is (a &#8211; b)(a &#8211; b)? When it is multiplied using FOIL, a<sup>2<\/sup> is a perfect square, and so is b<sup>2<\/sup>. The sign of 2ab is negative, because it is the sum of two negative products. Suppose the polynomial is 100x<sup>2<\/sup> \u2013 80x + 16. The square root of 100x<sup>2<\/sup> is 10x, and the square root of 16 is -4. The product of 10 and -4 is -40, and twice -40 is -80. That polynomial is (10x &#8211; 4)<sup>2<\/sup>.<\/p>\n<p>Figure 2: An example when the middle term is negative.<\/p>\n<p style=\"text-align: center\"><a href=\"https:\/\/schooltutoring.com\/help\/wp-content\/uploads\/sites\/2\/2014\/09\/negative-square-trinomial-pattern.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-6954 aligncenter\" src=\"https:\/\/schooltutoring.com\/help\/wp-content\/uploads\/sites\/2\/2014\/09\/negative-square-trinomial-pattern.jpg\" width=\"300\" height=\"157\" \/><\/a><\/p>\n<h3>Other Patterns<\/h3>\n<p>If the trinomial follows the form \u2013ax<sup>2<\/sup> +bx +c or ax<sup>2<\/sup> \u2013 bx \u2013 c or ax<sup>2<\/sup> + bx \u2013 c, it does not follow the squared trinomial pattern. The coefficient of a squared term cannot be negative even if the term is a perfect square. When a negative is multiplied by another negative, the product is positive. Similarly, if the constant c is not a perfect square, the trinomial does not follow the squared trinomial pattern.<\/p>\n<h3>Differences of Squares<\/h3>\n<p>The last special pattern to consider is (a + b)(a &#8211; b). Since multiplication is commutative, it is also the same as (a &#8211; b)(a + b). It is called the difference of squares. When (a + b)(a &#8211; b) is multiplied using FOIL, the first term is a<sup>2<\/sup>, and the last term is b<sup>2<\/sup>. The outside term is \u2013ab and the inside term is ab, which adds up as zero. They cancel each other out. Suppose a polynomial is 144x<sup>2<\/sup> + 81. The square root of 144x<sup>2<\/sup> is 12x and the square root of 81 is 9. Following the pattern, the factoring is (12x + 9)(12x &#8211; 9).<\/p>\n<p>Figure 3: An example of the form (a + b)(a &#8211; b).<\/p>\n<p style=\"text-align: center\"><a href=\"https:\/\/schooltutoring.com\/help\/wp-content\/uploads\/sites\/2\/2014\/09\/Difference-of-Squares.png\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-6954 aligncenter\" src=\"https:\/\/schooltutoring.com\/help\/wp-content\/uploads\/sites\/2\/2014\/09\/Difference-of-Squares.png\" width=\"300\" height=\"157\" \/><\/a><\/p>\n<p>Interested in <a href=\"https:\/\/schooltutoring.com\/math-tutoring\/algebra-1-tutoring\/\">algebra tutoring services<\/a>? Learn more about how we are assisting thousands of students each academic year.<\/p>\n<p><span class=\"tutorOrange\">SchoolTutoring Academy<\/span> is the premier educational services company for K-12 and college students. We offer tutoring programs for students in K-12, AP classes, and college. To learn more about how we help parents and students in Spearfish, SD: visit <a href=\"https:\/\/schooltutoring.com\/tutoring-in-spearfish-south-dakota\/\">Tutoring in Spearfish, SD<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview Trinomial squares are also known as perfect square trinomials, and are the squares of binomial expressions. They factor as (a + b)(a + b) or (a &#8211; b)(a &#8211; b) where a and b are real numbers. Forms such as (a + b)(a -b) are special products that are also called the difference of [&hellip;]<\/p>\n","protected":false},"author":22,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"categories":[2],"tags":[2725,2635],"class_list":["post-7448","post","type-post","status-publish","format-standard","hentry","category-algebra","tag-difference-of-squares","tag-perfect-square-trinomial"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/posts\/7448","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/users\/22"}],"replies":[{"embeddable":true,"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/comments?post=7448"}],"version-history":[{"count":0,"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/posts\/7448\/revisions"}],"wp:attachment":[{"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/media?parent=7448"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/categories?post=7448"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/schooltutoring.com\/help\/wp-json\/wp\/v2\/tags?post=7448"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}