X^2-5x-6
X^2+3x-40
X^2+3x-4

x² - 5x - 6

= x² + x - 6x - 6

= x(x + 1) - 6(x + 1)

= (x - 6) (x + 1)

x² + 3x - 40

= x² + 8x - 5x - 40

= x(x + 8) -5(x + 8)

= (x - 5) (x + 8)

x² + 3x - 4

= x² + 4x - x - 4

= x(x + 4) -1(x + 4)

= (x - 1) (x + 4)

assuming you mean addition: addition and subtraction are reverse operations.

step-by-step explanation:

for the friend request.

when a figure, such as triangle (xyz) is reflected over the line y = x to create x'y'z' the x-coordinates and y-coordinates of the original image (pre-image) will be reversed for the image. (e.g., (x, y) > (y, x)) this means that the pre-image position of the x- and y-coordinates switch places which in turn provides a mirror like image of the original xyz.  

i notice that when i draw a line segment from x to x', that the points are parallel from each other -- they are exactly across from each other and do not intersect with any other points.  

yes, think i would see the same characteristic if you drew the line segment connecting y with the reflecting line and then y' with the reflecting line because of the essence of reflections. because it is a mirror image, each point was effected the same way which leads me to conclude that they same would apply to y and y'.