REFRESHER IV Equations
Analgebraic expression consists of variables (letters), numbers, operation
signs (þ, ,,), and grouping symbols. Here are a few examples of
algebraic expressions:
3 x 5(x5) 8 x^29 þ 2Anequationis a statement of equality of two algebraic expressions. Here
are some examples of equations:
5 þ 4 ¼ 93 x 2 ¼ 13 x^2 þ 3 xþ 2 ¼ 0An equation which contains a variable is called aconditionalequation. To
solvea conditional equation, it is necessary to find a number which, when
substituted for the variable, makes a true equation. This number is called a
solutionto the equation. For example, 5 is a solution to the equationxþ 3 ¼8,
since when 5 is substituted forxit makes the equation true, i.e., 5þ 3 ¼8.
The process of finding a solution to an equation is calledsolvingthe equation.
The same number (except zero) can be added to, subtracted from,
multiplied by, or divided into both sides of the equation without changing the
nature of the equation.
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