The use of different modes (e.g., words, mathematical symbols, images) is central to encounter different perspectives of the same mathematical idea, and a combination of different modes generally contribute to a deeper understanding, than each mode separately (O'Halloran, 2005). At the same time, research has shown that combinations of modes, e.g., in mathematical textbooks, are challenging for students to interpret (Norberg, 2019). This on-going study contributes to the fields understanding of the complexity of interplay between modes by using Engebretsen’s (2012) theory of the necessity of balance between cohesion and tension to analyse how modes are used when introducing new mathematical ideas in textbooks.We have delimited our analysis to the introduction of equality and of subtraction in three commonly used textbooks for first grade students. Figure 1 shows an example of an introduction of equality. In this example, we identified one type of cohesion between the use of circles (images) in two groups, the numerals with an equal sign between (symbols), and the words “equal numbers” and “is equal to” in the yellow box. These modes address the same objects in the same way, that is, there is cohesion. At the same time, there are no symbols present in the exercise below. Students should only circle an equal number of objects found in the picture. Thus, there is a type of tension between the yellow box and the exercise since the different modes do not have the same role in these different parts. Further analysis will identify different types of cohesion and tension between modes, before examining how these are handled by students.