Download Geo Reminders for ACT - Ms-Schmitz-Geometry

Geometry Reminders for ACT
Special Pairs of Angles
Linear Pairs - supplementary and form a line
Vertical Angles - congruent
Complementary Angles - a pair of angles that add up to 90º
Supplementary Angles - a pair of angles that add up to 180º
Parallel Lines and Transversals
All pairs of angles are either congruent or supplementary
Alternate Interior angles - congruent
Alternate Exterior angles - congruent
Corresponding angles - congruent
Consecutive Interior angles - supplementary
Triangles
Isosceles Triangles - 2 sides congruent, base angles congruent
Equilateral Triangles - all sides congruent, all angles 60º, altitude makes a 30-60-90 triangle
Angles across from the biggest side of a triangle are the biggest angle and vice versa
Angles across from the smallest side of a triangle are the smallest angle and vice versa
Angles add up to 180
Right Triangles
a2  b2  c2
hypotenuse
leg

leg
section adjacent to leg
Pythagorean Theorem - use when you know 2 sides of a right triangle
section 1 altitude

section 2
Geometric Mean - altitude
opposite
hypotenuse
Quadrilaterals
sin  
cos  
adjacent
hypotenuse
tan  
opposite
adjacent
Geometry Reminders for ACT
Parallelograms - opposite sides parallel, opposite sides congruent, opposite angles congruent,
consecutive angles supplementary, diagonals bisect each other
Rectangles - all parallelogram properties, diagonals congruent, all angles right angles
Rhombus - all parallelogram properties, diagonals perpendicular, all sides congruent
Squares - all properties of parallelograms, rectangles and rhombus
Circles
All radii are congruent
Radius is perpedicular to a tangent at point of tangency
Radii that are perpendicular to chords bisect chords
Diameters make semi-circles which are 180º
2 radii and a chord make an isosceles triangle
Angle and Segment Formulas click here
Area
Formulas at: click here
Surface Area and Volume
Formulas at: click here