There is only one unknown, and the number of unknowns is 1. Such an equation is called a one-dimensional linear equation, and usually takes the form of ax+b=0(a, B are constants, and a≠0).

Equations with unknowns are called equations. To judge whether a formula is an equation, we need to pay attention to two aspects. First, it is an equation, that is, a formula with "=" cannot be an inequality, that is, it cannot have "800;" , > "and other unequal symbols.

1, the value of the unknown that makes the left and right sides of the equation equal is called the solution of the equation. To judge whether a number (or a group of numbers) is the solution of an equation, we only need to look at two points. Substitute it into the left and right side of the equation. If left equals right, they are the solutions of the equation, otherwise they are not.

2. Properties of the equation 1: The equation still holds when a number is added to both sides of the equation or the same number or the same algebraic expression is subtracted. Both sides of the equation expand or contract at the same time by the same multiple (except 0), and the equation still holds. Multiply (or square) both sides of the equation at the same time, and the equation still holds. ?

3. Solving the equation is based on three properties of the equation. The first property of the equation: adding a number or subtracting the same number on both sides of the equation at the same time, the equation still holds. The steps to solve the equation are denominator, brackets, shifting terms, merging similar terms, and converting the coefficient into 1.