What is the sum of the interior angles of a polygon with n sides?

(n - 2) × 180°. For example, a hexagon (6 sides) has interior angles summing to 720°.

In a 30-60-90 triangle, if the shorter leg has length x, what are the lengths of the longer leg and hypotenuse?

The longer leg is x√3 and the hypotenuse is 2x.

What does the Triangle Inequality Theorem state?

The sum of any two sides of a triangle must be greater than the third side.

What is the formula for the area of a triangle given two sides and the included angle?

Area = (1/2)ab·sin(C), where a and b are the two sides and C is the included angle.

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ACT Geometry & Trigonometry Mastery

Master every Geometry and Trigonometry concept tested on the ACT with these 28 targeted flashcards. Covering angles, triangles, circles, coordinate geometry, and trigonometric functions, this deck prepares students to confidently tackle the math section. Each card focuses on a single testable concept with clear, concise answers.

28 cards Intermediate Triangles & Polygons Circles Coordinate Geometry 3D Geometry & Area/Volume Trigonometry

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