How to find the length and the width of this rectangle? Thanks!
1 Answer
Apr 20, 2018
Explanation:
#"since area "="length "xx"width"#
#"then the product of the factors of "2x^2+13x+21#
#"are the length and width"#
#"factoring using the a-c method"#
#"which sum to + 13 are + 6 and + 7"#
#"split the middle term using these factors"#
#2x^2+6x+7x+21larrcolor(blue)"factor by grouping"#
#=color(red)(2x)(x+3)color(red)(+7)(x+3)#
#"take out the "color(blue)"common factor "(x+3)#
#=(x+3)(color(red)(2x+7))#
#"the length and width are "x+3" and "2x+7#