Unit 5 - Geometry
Line of Symmetry - an imaginary line down the center of a figure that creates a perfect mirror image.
Geometric Shapes and Measurement
How to use a protractor:
Put the vertex in the center.
Line up the bottom ray along the bottom of the protractor.
Look at the second ray. What numbers is it going through?
Is your angle acute or obtuse? Pick the correct measurement.
Adjacent Angles - angles that share a ray.
You can find the measurement of adjacent angles without a protractor if you know some of the measurements.
This image does not tell you the measure of the biggest angle there, but if you add 30 + 60 you will get the measurement. It is 90 degrees.
Use the websites below to practice measuring angles.
www.mathplayground.com/measuringangles.html
www.mrnussbaum.com/protractor/
Use the following website to practice measuring objects with metric and customary units.