1. Ratios, Proportions, and Similar Triangles

2. Ratios Ratios are like fractions The ratio 1:4 means 1 part to 4 parts and is equivalent to the fraction (part:part) OR(part:whole, because there are 5 parts altogether)

4. Ratio Word Problems Attach an X to each part of the ratio Write and solve an equation using the expressions 3.The ratio of two complementary angles is 1 : 2. Find the angles. <1 = 1x, <2 = 2x 1x + 2x = 90 3x = 90; x = 30 <1 = 30, <2 = 60 4.The ratio of two supplementary angles is 4 : 1. Find the angles. 5.The ratio of the angles of a triangle is 2 : 3 : 7. Find the angles.

5. A. Solving Proportions Cross multiply and set the products equal to each other Be sure to use FOIL when multiplying polynomials Solve for the variable

6. B. Properties of proportions

7. Similar Polygons Example of similar triangles Their corresponding angles are _______________. Their corresponding sides are in a ___________________. This ratio is called a _______________ and in this case is ____. We show that they are similar with this statement: ____________. shapesize scale factor2:1 congruent direct ratio