Similar Triangles

Similar Triangles

1. Use similarity rule to match up corresponding sides.

2. Set up a proportion with fractions of correspoinding sides

3. Solve by cross multiplying (or easiest algebra method for you)

​Example:

​If ΔAGM ∼ ΔKXD, find the value of x.

Scale Factor

Scale Factor

1. Identify preimage (old) and image (new)

2. Set up a fraction k of coresponding sides or points.

3. Reduce the fraction

​Example:

Dilation

Dilation of Coordinates

Example

Find the new coordinates after the following transformation:

dilation of 3/2 about the origin

E(-1,2), F(1, 3), G(2, 0)

1. Multiply each x and y coordinate in the ordered pair by the scale factor.