Solving Systems Using Substitution: Interactive GeoGebra Practice

① This example demonstrates how to solve a system of two linear equations using the substitution method, with an interactive GeoGebra interface that lets users input coefficients and instantly see the solution and graphical verification. ② Core math concepts include substitution elimination for linear systems, equation manipulation, uniqueness of solutions, and the correspondence between algebraic solutions and geometric intersection points of lines. ③ Construction highlights: from the summary, commands such as Sequence, RandomElement, Simplify, LaTeX, Textfield, and Segment are used; objects like leftlist, rightlist, list1, list2 store equation sides, while InputBoxes and a button trigger calculations, with text objects displaying the simplified steps and solution. ④ Suitable for middle school to high school students learning algebra, and useful for teachers in classroom demonstrations or for self-paced practice, reinforcing both procedural steps and geometric interpretation.