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Define It: Math Terms

Question: Share
Answer: Two polygons that touch along one side share that side.
Question: Split
Answer: Division is used to split a number into parts. To split 12 into four parts, 12 is divided by 4: 12 ÷ 4 = 3.
Question: Right angle
Answer: A right angle is 90°.
Question: More
Answer: If Juan has 11 apples and Tanya has 15, Tanya has 4 more apples than Juan has.
Question: Rhombus
Answer: The area of a rhombus can be found by multiplying the lengths of the diagonals and then dividing by 2.
Question: Symmetry
Answer: A shape has symmetry if it can be folded so that its two sides match evenly.
Question: Quotient
Answer: In 6 ÷ 2 = 3, 3 is the quotient.
Question: Times
Answer: In 2 × 3 = 6, × is the times sign.
Question: Change
Answer: If the item costs $5.50 and Alex gives the clerk $10.00, Alex will receive $4.50 in change.
Question: Acute angle
Answer: An acute angle measures less than 90°. Ace this question? Try our Mathematics: Fact or Fiction Quiz.
Question: Remainder
Answer: Also called the leftover, a remainder is the amount “left over” after dividing one integer by another to produce an integer.
Question: Fraction
Answer: A fraction represents the quotient of two numbers—the division of one number (the numerator) by another (the denominator)—such as ½ or ⅔.
Question: Difference
Answer: In 6 − 2 = 4, 4 is the difference.
Question: Isosceles triangle
Answer: The area of an isosceles triangle can be found by multiplying the length of the base by the height and then dividing by 2.
Question: Numerator
Answer: In ⅔, 2 is the numerator of the fraction.
Question: Combine
Answer: Combining 3 with 7 results in 10.
Question: Circle
Answer: A circle is a geometrical curve consisting of all points in a plane that are the same distance (radius) from a given point (the center).
Question: Separate
Answer: A group of 20 people can be separated into four groups of 5 people each.
Question: Pentagon
Answer: The Pentagon is a building in Arlington, Virginia, named for its five sides.
Question: Scalene triangle
Answer: A scalene triangle has three sides of unequal length and three unequal angles.
Question: Circumference
Answer: Circumference can be found by multiplying the diameter of a circle by π (roughly 3.14).
Question: Straight angle
Answer: A straight angle appears as a straight line.
Question: Congruent
Answer: Two congruent angles have the same measure.
Question: Angle
Answer: The point at which two lines intersect is called the vertex.
Question: Octagon
Answer: The area of a regular (equal-sided) octagon equals 2(1 + √2)a2. The symbol a represents the length of one side.
Question: Factor
Answer: Since 6 × 3 = 18, 6 and 3 are factors of 18.
Question: Decreased
Answer: If a number has decreased, another number has been subtracted from it.
Question: Ray
Answer: A ray has a fixed starting point but no endpoint. If you aced this question, try our Numbers and Mathematics Quiz.
Question: Addend
Answer: In 6 + 3 = 9, 6 and 3 are the addends.
Question: Plus
Answer: In 6 + 2 = 8, + is the plus sign.
Question: Integer
Answer: If an integer is subtracted from itself, the result is zero, and if a larger integer is subtracted from a smaller one, the result is a negative integer.
Question: Equilateral triangle
Answer: When shapes other than a triangle have all equal sides, they are identified by the word regular. All equilateral triangles are isosceles triangles, but not all isosceles triangles are equilateral triangles.
Question: Line segment
Answer: A line segment includes all points of the line between its two endpoints.
Question: Quarter
Answer: The quarter of a number divisible by four can be found by dividing the number by four—for example, 16 ÷ 4 = 4.
Question: Sum
Answer: In the equation 2 + 3 = 5, 5 is the sum.
Question: Parallel
Answer: Two lines that will never cross each other are parallel.
Question: Cube
Answer: 27 is the cube of 3 because 33 = 3 × 3 × 3 = 27.
Question: Prime
Answer: Prime numbers include 2, 3, 5, 7, 11, 13, and others.
Question: Area
Answer: The area of a square can be found by multiplying the length of one side by itself.
Question: Probability
Answer: The probability of an event occurring can range from zero to one.
Question: Product
Answer: The product of 6 and 3 is 18.
Question: Less
Answer: One expression of 4 less than 10 is 10 − 4.
Question: Square
Answer: A polygon having sides of 6 units each and four 90° angles is a square.
Question: Perpendicular
Answer: Two lines are perpendicular if they intersect at a right angle.
Question: Perimeter
Answer: Perimeter is the sum of all the sides of a plane area.
Question: Mode
Answer: In a set of numbers, the mode is the number that appears the most often.
Question: Denominator
Answer: In ⅔, 3 is the denominator of the fraction.
Question: Mean
Answer: The mean of a set of numbers is found by adding up all the numbers and then dividing the sum by how many numbers there are.
Question: Total
Answer: When adding numbers, the total is the same as the sum.
Question: Average
Answer: Of the measurements 2 meters, 7 meters, and 9 meters, the average length is 6 meters.
Question: Median
Answer: In a set of numbers listed in ascending order, the median is the number in the middle position.
Question: Leftover
Answer: Also called the remainder, a leftover is the amount “left over” after dividing one integer by another to produce an integer.
Question: Intersecting lines
Answer: Intersecting lines have angles at their point or points of intersection.
Question: Half
Answer: Since 4 ÷ 2 = 2, 2 is half of 4. Ace that question? Try our Fun Facts of Measurement and Math Quiz.
Question: Coordinate
Answer: A point on a two-dimensional line graph is usually represented as a pair of coordinates (x, y) that correspond to a position on the graph’s x (horizontal) and y (vertical) axes.
Question: Estimate
Answer: An estimate does not provide the exact value of something.
Question: Fewer
Answer: If Willis has 8 fewer papers than Janet has and she has 11 papers, Willis has 3 papers.
Question: Polygon
Answer: Polygons have no curves or openings.
Question: Volume
Answer: For a cube, volume equals length × width × height.
Question: Together
Answer: The numbers 6 and 3 together make 9.
Question: Parallelogram
Answer: Squares, rectangles, and rhombuses are all parallelograms.
Question: Quadrilateral
Answer: That’s the only qualification a polygon needs to be a quadrilateral: four sides.
Question: Increased
Answer: If 5 is increased by 2, the result is 7.
Question: Expression
Answer: An expression uses numerals, operators (such as + or ÷), and other symbols (such as a letter for an unknown value) to represent a quantity. It does not include an equal sign.
Question: Obtuse angle
Answer: An obtuse angle is sometimes identified as a “fat” angle. If you aced this question, test your skills on our All About Math Quiz.
Question: Hexagon
Answer: The area of a regular (equal-sided) hexagon equals [(3√3)/2] × a2. The symbol a represents the length of one side.
Question: Equation
Answer: An equation must include an equal sign.