**Decide whether a number is a solution of a linear**

**equation. **If the variable in an equation can be replaced by a real number

that makes the statement true, then that number is a **solution **of the equation.

For example, 8 is a solution of the equation *x *– 3 = 5, since replacing *x*

with 8 gives a true statement, 8 – 3 = 5. An equation is *solved *by finding

its **solution set, **the set of all solutions. The solution set of the equation

*x *– 3 = 5 is {8}.

**Equivalent equations **are equations that have the same solution set. To

solve an equation, we usually start with the given equation and replace it

with a series of simpler equivalent equations. For example,

5*x *+ 2 =17, 5*x *= 15, and *x *= 3 Â Equivalent equations

are all equivalent since each has the solution set {3}.