Math 4 review

• Prime numbers are counting numbers that have two distinct factors (1 and itself)
• Composite numbers are counting numbers that have more than two distinct factors.
• Prime factorization is an expression of a composite number as a product of its prime factors.
• Greatest common factor (GCF) - the largest common factor of two or more numbers.
• Least common multiple is the smallest common multiple of two or more numbers.
• Acute angles are angles that are less than 90 degrees.
• Right angles are angles the measure only to 90 degrees.
• Obtuse angles are angles that are greater than 90 degrees.
• Parallel lines are lines that do not meet at any point
• Perpendicular lines are lines that intersect at right angle
• Intersecting lines meet at only one point.
• Triangle is the polygon with 3 sides and 180 degrees.
• Equilateral triangles have sides that are all equal
• Isosceles triangle has two sides that are equal
• Scalene triangle has no two sides that are of the same length.
• Acute triangles are scalene triangles with each side less than 90 degrees.
• Right triangle: A triangle with a 90° angle.
• Obtuse triangle: A triangle with an obtuse angle (greater than 90°).
• Polygon is a closed plane figure.
• Regular polygons is a polygon with all sides and angles congruent (equal)
• Irregular polygons has no equal sides.
• Congruent polygons are two polygons of the same size and shape.
• Similar polygons are two polygons with the same shape but not the same size.
• Quadrilateral is a 4 sided polygon
• Square: Quadrilateral with right angles and equal sides.
• Rectangle: Quadrilateral with right angles.
• Rhombus: Quadrilateral with equal sides.
• Parallelogram: Quadrilateral with opposite parallel sides.
• Trapezoid: Quadrilateral with one pair of parallel sides.
• Triangle: Area = 1/2 bh and Perimeter = a+b+c
• Square: Area=S² & Perimeter=S4
• Rectangle: Area=lw & Perimeter=2(l+w)
• Perimeter is the distance around a polygon.
• Area is the amount of space occupied in a figure