Which facts could be applied to simplify this expression? check all that apply. (-5x--3z).

to subtract like terms, subtract the coefficients, not the variables.
like terms are terms that contain the same variable, raised to the same power.
the simplified expression is -6x-3y+3z.
only combine terms which contain the same variable.
) is equivalent to -x, so -5x-x=-6x.
the simplified expression is -4x-3y+3z

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'.