In algebra, an equation is an expression of the shape A = B, where A and B are algebraic expressions with one or more unknown variables. Students often confuse an algebraic equation with equality, but they are two distinct terminologies. An equality is a mathematical statement that states that the expression on the left hand side, when simplified, should be equal to the expression on the right hand side, and it does not involve any unknown variable. An equation, on the other hand , is not a statement; rather, it is a problem comprising one or more unknown variables, whose values, called solutions, are to be determined on the basis of the relationship given in the equation. For example, 3x + 5 = 2 is an equation, with one unknown “x”.
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