This method of solving a quadratic equation with one variable is called collocation method.

1. transformation: transform the unary quadratic equation into the form of ax 2+bx+c = 0 (that is, the general form of unary quadratic equation).

2. Coefficient 1: set the coefficient of quadratic term as 1.

3. Move the item: move the constant item to the right of the equal sign.

4. Formula: The left and right sides of the equal sign are added with the square of half of the first coefficient.

5. Deformation: Write the algebraic expression on the left of the equal sign as a complete square.

6. Square root: simultaneous square root.

7. Solution: The root of the original equation can be obtained by sorting.

Write in the form of (a+b) square or (a-b) square: expand (a+b) square into (a+b) 2 = a 2+2ab+b 2. Therefore, to match the form of (a+b), a 2, 2ab and b 2 must be selected.