Addition : Addition is the mathematical operation that describes increasing a number by an amount equal to a second number. The mathematical symbol for addition is the plus sign $+.$ The term addition is also used for a generalization of this basic operation on numbers to functions, vectors and matrices.

Ones digit : The first digit left of the decimal point (or the digit furthest to the right if there is no decimal point). It counts multiples of 1.

Ten : Ten refers to the number $10.$

Area : The amount of unit squares that is needed to cover a 2-dimensional shape.

Inch : An inch or $in$ is a unit of measurement for length. 12 inches are one foot and 1 inch is about 2.54 $cm.$

Length : Length is the attribute of a one-dimensional shape that can be measured with a measuring tape.

Product : A product is the result of a multiplication.

Rectangle : A rectangle is a quadrilateral with 4 right angles. Two opposing sides in a rectangle have the same length. They are sometimes referred to as the width and the length of the rectangle. To calculate the area of an rectangle one can multiply the width of the rectangle by the length of the rectangle. A square is the special case of a rectangle in which all side lengths are the same. Every rectangle is a parallelogram.

Square inch : Square inch is a unit of measurement for measuring area. 1 square inch is the area of a square with side length 1 inch. 144 square inches are 1 square foot.

Negative : A number is negative if it is $\lt 0.$

Number : A number $x$ is a mathematical symbol representing a quantity.

Positive : Positive means $\geq 0.$