If two parallel lines are cut by a transversal so the alternate interior angles are (congruent, supplementary, complementary), then the lines are parallel.

If two parallel lines are cut by a transversal so the alternate interior anglesare congruent, then the lines are parallel.

The point where two lines meet is known as an angle

For two parallel lines that are transversal, some of the angles are equal i.e. they are congruent to each other.

We can have the following as shown in the figure;

Hence we can conclude that if two parallel lines are cut by a transversal so the alternate interior angles are congruent, then the lines are parallel.

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if two parallel lines are cut by a transversal so that the alternate interior angles are congruent, then the lines are parallel.

a.   since the profit made in 2012 is equal to the profit made in 2014, the profit is symmetric about the line y = 120,000.

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'.