Triangle congruence
Triangles are congruent if SSS, SAS, ASA, or AAS holds, or HL for right triangles.
Try it: Two triangles have three pairs of equal sides. Which rule applies?
Show answer
SSS.
Lessons by subject. Read the lesson, try the question, then check your answer.
Topics follow the Georgia Standards of Excellence, the state's current standards (they replaced the older Common Core Georgia Performance Standards). This is an unofficial study aid, not a Coffee County Schools resource. Your teacher's pacing guide and textbook come first. Official standards: georgiastandards.org.
Triangles are congruent if SSS, SAS, ASA, or AAS holds, or HL for right triangles.
Try it: Two triangles have three pairs of equal sides. Which rule applies?
SSS.
Similar triangles have equal angles and proportional sides. If one triangle has sides 3, 4, 5 and a similar one has sides 6, 8, x, then x = 10.
Try it: Triangles with corresponding sides 2 and 6, and 5 and x, are similar. Find x.
15, because the scale factor is 3.
SOH-CAH-TOA: sin = opposite ÷ hypotenuse, cos = adjacent ÷ hypotenuse, tan = opposite ÷ adjacent.
Try it: In a right triangle with legs 3 and 4 and hypotenuse 5, what is the sine of the angle opposite the side of length 3?
3/5.
Circumference = 2πr and area = πr². For r = 5, C = 10π and A = 25π.
Try it: Find the area of a circle with radius 3.
9π.
Early civilizations grew along rivers: the Nile (Egypt), the Tigris and Euphrates (Mesopotamia), the Indus, and the Yellow River (Huang He) in China.
Try it: Which river supported ancient Egypt?
The Nile.
The Silk Road connected China with the Mediterranean, moving goods like silk and spices along with ideas and religions.
Try it: What traveled along the Silk Road besides goods?
Ideas, religions, and technology.
Climate is affected by latitude, elevation, nearness to oceans, and ocean currents.
Try it: Why is it usually colder high in the mountains?
Temperature drops as elevation increases.
A biome is a large region with similar climate and life, such as tropical rain forest, desert, tundra, or temperate forest.
Try it: Which biome is cold and treeless?
Tundra.
Ethos appeals to credibility, pathos to emotion, and logos to logic.
Try it: A speaker cites statistics. Which appeal is that?
Logos.
A credible source has an expert author, current information, evidence, and few signs of bias. Check who wrote it and why.
Try it: Name one sign that a source is credible.
An expert author, cited evidence, or current information.
Synthesis combines ideas from several sources to support your own argument rather than just summarizing each one.
Try it: What is the difference between summary and synthesis?
Summary restates one source. Synthesis connects several sources to make a point.
Use parallel structure and vary sentence length. Parallel: She likes hiking, biking, and swimming.
Try it: Make parallel: He likes to run, swim, and biking.
He likes to run, swim, and bike.