Review Chapter 4

Ratio and Rates 4.1

Vocabulary Ratio – a comparison of two numbers by division. Rate – a comparison of two quantities with different types of units Unit Rate – a rate that has been simplified so it has a denominator of 1.

Rate of Change 4.2

Vocabulary Rate of change – a rate that describes how one quantity changes in relation to another.

Rate of Change

Rate of Change Graphs

Slope 4.3

Vocabulary Slope – the rate of change between two points Rise – the vertical change Run – the horizontal change

Solving Proportions 4.4

Vocabulary Proportion – two ratios that are equivalent. Cross Products – the process of multiplying two ratios for comparison or solution.

Proportion PROPORTION:

Cross Products CROSS PRODUCTS:

Using Cross-Products To Solve Set your two proportions to be equal Use your cross-products to set up the equation Multiplication problem: Divide X equals your missing denominator!

Similar Polygons 4.5

Vocabulary Polygon – a simple closed figure in a plane formed by three or more line segments Similar – polygons that have the same shape Corresponding parts – parts of similar figures that “match” Congruent – angles that have the same measure Scale factor – the ratio of the lengths of two corresponding sides of two similar polygons

Properties of Similar Polygons

Similar Polygons

Scale

Scale Drawings and Models 4.6

Vocabulary Scale drawing – a 2 dimensional representation of an object that is too large or too small to be drawn or built at actual size. Scale Model – a 3 dimensional representation of an object that is too large or too small to be drawn or built at actual size. Scale – the ratio of the given length on a drawing or model to its corresponding actual length. 1 inch = 4 feet 1:30 = 1 unit represents an actual distance of 30 units.

Indirect Measurement 4.7

Vocabulary Indirect measurement – the technique of using properties of similar polygons and proportions to find distances or lengths that can be difficult to measure directly.

Shadow Reckoning

Dilations 4.8

Vocabulary Dilation – the image produced by enlarging or reducing a figure

Scale Factor