The Answer is <span>(x−2)</span><span>(3x+5<span>)</span></span>
X^4 - 5x^2 - 36 = 0
(x^2 - 9)(x^2 + 4) = 0
(x-3)(x+3)(x-2)(x+2) = 0
x = -3, -2, 2, 3
Think of the entire population of 6th graders here. 3/7 are boys and 4/7 are girls. 5/8 of these boys are in Ms. Jones' class; that fraction would be (5/8)(3/7), or 15/56. This 15/56 represents the fraction of the entire sixth grade class who are in Ms. Jones' class.
Lets set up the relationship of the length to width:
l = 3w
Using this, we can make all the variables the same by substitution:
2l + 2w = perimeter
2l + 2w = 72
2(3w) + 2w = 72
6w + 2w = 72
8w = 72
w = 9
The width is 9, to the length must be 9*3, or 27.
Hope this helped!