Analisis Kesalahan Dalam Menyelesaikan Soal Operasi Aljabar Pada Siswa Kelas Vii Di Smp Negeri 2 Delanggu

The object of this research is to describe students wrong in solving algebraic surgery VII class SMP N 1 Delanggu in 2018/2019 years. This research used descriptive qualitative method. Technique of collecting data by test method, interview and documentation. The data validity investigation used triangulation method, is by collecting different data to get data from the same source through tests, interviews and documentation. Technique of analyzing data through data reduction phase, data presentation and conclusion. Based on the analysis data and discussion student experience errors are: (1) trandformation error or Transformation Error includes errors in identifying operations or sequence of operations , (2) the error of process skill or Process Skill Error include (a) error in carryingout the calculation operation correctly or inaccurately (b) error in counting (3) Error of writing final answer or Encoding Error includes mistakes not able to find the final result of the question correctly. Factors that cause students to make mistakes in solving problems include students are not careful in operating algebra, lack of ability to solve problems that exist in the algebraic problem, not knowing the exact sequence of operations in solving the problem, unable to understand the concept of calculating correctly and in a hurry in writing the final answer