A letter that stands for a number in an expression or an equation is called a

An __________ signifies a combination of numbers, variables, and operation symbols.

What is the branch of Mathematics in which letters and other general symbols are used to represent numbers and quantities in formulae and equations?

In the expression, the ______followed by the values, cell address and functions are called as formula.

In a chemical equation, the symbol that takes the place of the word yields is a(n)plus sign.coefficientarrow.

In mathematical reasoning it is often necessary to make statements about objectsthat are represented by letters called variables. For example, if the variable xis used to stand for a number in some problem, we might be interested in thestatement “x is a prime number.” Although we may sometimes use a singleletter, say P, to stand for this statement, at other times we will revise thisnotation slightly and write P(x), to stress that this is a statement about x.The latter notation makes it easy to talk about substituting some number forx in the statement. For example, P(7) would represent the statement “7 is aprime number,” and P(a + b) would mean “a + b is a prime number.” If astatement contains more than one variable, our abbreviation for the statementwill include a list of all the variables involved. For example, we might representthe statement “p is divisible by q” by D( p, q). In this case, D(12, 4) wouldmean “12 is divisible by 4.”Although you have probably seen variables used most often to stand fornumbers, they can stand for anything at all. For example, we could let M(x)stand for the statement “x is a man,” and W (x) for “x is a woman.” In thiscase, we are using the variable x to stand for a person. A statement might evencontain several variables that stand for different kinds of objects. For example,in the statement “x has y children,” the variable x stands for a person, and ystands for a number.Statements involving variables can be combined using connectives, just likestatements without variables.Example 1.3.1. Analyze the logical forms of the following statements:1. x is a prime number, and either y or z is divisible by x.2. x is a man and y is a woman and x likes y, but y doesn’t like x