Abilities and Difficulties of Ninth-Grade Students in Solving Geometry Transformation Problems

Abstract

Abstract: Geometry is one of the challenging subjects for students. This study aimed to determine the ability of students to solve geometric transformation problems, the difficulties they experienced, and the causes. This research employed a mixed method with a sequential explanatory design. Eight Year 9 students were the subjects of this study. Data were collected through tests and interviews. The data were analyzed quantitatively, followed by qualitative analysis involving reducing data, presenting data, and concluding. The results indicated that the students ability to solve geometric transformation problems was moderate. Students found it difficult to solve geometric transformation problems. The students difficulties included determining the translation when a starting point and an image point were given and determining the image of a point/curve by a transformation. Students had not fully mastered the schemes in the geometric transformation, were not proficient in using formulas, and were not precise in their calculations.    

Keywords students’ difficulty, transformation, translation, rotation, dilatation.

Abstrak Geometri adalah salah satu topik yang sulit bagi siswa. Tujuan penelitian ini yaitu mengetahui kemampuan siswa dalam menyelesaikan soal transformasi geometri dan kesulitan yang dialami oleh siswa serta penyebab terjadinya kesulitan dalam menyelesaikan soal transformasi geometri. Penelitian menggunakan pendekatan Mixed Method dengan jenis explanatory sequential. Subjek penelitian ini adalah 8 siswa kelas IX. Teknik pengumpulan data yaitu tes dan wawancara. Data dianalisa secara kuantitatif, kemudian kualitatif dengan mereduksi data, menyajikan data, dan menarik kesimpulan. Hasil penelitian mengindikasikan kemampuan siswa dalam menyelesaikan soal transformasi geometri tergolong kategori sedang. Hal ini mengindikasikan siswa masih sulit dalam menyelesaikan soal transformasi geometri. Adapun kesulitan siswa yaitu menentukan translasi jika diberikan sebuah titik awal dan titik bayangan, menentukan bayangan suatu titik/kurva oleh suatu transformasi. Penyebabnya yaitu siswa belum sepenuhnya menguasai skema yang ada di dalam transformasi geometri, tidak mahir menggunakan rumus, dan tidak tepat perhitungannya.  

Kata kunci kesulitan, geometri, translasi, rotasi, dilatasi.

DOI: http://dx.doi.org/10.23960/jpmipa/v23i2.pp1724-1737