The length of each side of an equilateral triangle is increased by 5 inches so the perimeter is now 60 inches. write and solve an equation to find the original length of each side of the equilateral triangle.

A trainee has 3 sides and each side was increase by 5 inches.

Let x be the length of one side. You need to subtract 15 from the perimeter:

The equation can be 3x = 60 -15

Simplify:

3x = 45

Divide each side by 3:

X = 15

The original length of each side was 15 inches.

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'.