## Reflection: Writing Across the Disciplines Area of Triangles - Section 3: New Formula for Area of Triangles

Today, my students struggled with writing an argument. Some students could not take the numerical reasoning done during the activity and through repeated reasoning produce a generalization. Others could state the formula, but had trouble writing out a process others could follow. Here is a sample of a students first attempt at writing an argument.

My approach was to have one student put up an argument. The class discussed and critiqued the argument. This helped students to better communicate their own reasoning. However, the lesson helped me to recognize that my students need more practice with writing explanations of problem solving processes.

Writing Across the Disciplines: Writing an argument

# Area of Triangles

Unit 6: Solving Problems Involving Triangles
Lesson 10 of 13

## Big Idea: Why does (1/2)*a*b*sin(C) give the area of a triangle?

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3 teachers like this lesson
Standards:
Subject(s):
Math, Trigonometry, triangles (Determining Measurements), area of triangle, problem solving, pre
45 minutes

### Katharine Sparks

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