Abstract This study aimed to find the effectiveness of using strategy in based on m scan dimensions in algebraic reasoning and mathematical confidence of nine grade students. To verify this, a teacher's guide was prepared for teaching the unit of functions and equations using the strategy, and the algebraic reasoning test and the mathematical confidence scale were used, and their validity and reliability were verified. The researcher has also prepared a test to measure the algebraic reasoning, and its validity and reliability were checked and verified. The sample of the study consisted of (60) female students of the ninth grade in a basic education school in Al-Dhahera Governorate. They were divided into two groups: an experimental group who studied the unit of functions and equations using strategy in based on M-Scan dimensions, and a control group who studied the same unit using the usual teaching method. The study found the following results: - There is a statically significant difference at the level of significance (α= 0.05) between the mean scores of the experimental group and the mean scores of the control group in the post-application of the test in favor of the experimental group. - There is a statically significant difference at the level of significance (α= 0.05) between the mean scores of the experimental group and the mean scores of the control group in the post-application of the mathematical confidence scale in favor of the experimental group. Considering these results, the researcher recommended the importance of applying and using strategy in based on M-Scan dimensions in teaching the mathematics subjects in general. Based on the positive effects the study had shown on algebraic reasoning among the students.