## High School: Writing Equations

**Background Information**:

This high school algebra class is studying equations and the teacher gave them a triangle with the measures of the individual angles it represented by algebraic expressions rather than numbers. This math lesson is taking place at the beginning of the year and the segment assumes that the students have learned the difference between an expression and an equation. The lesson is concentrating on the following learning standard (SOL):

SOL:The student will represent quantitative situations algebraically and evaluate these expressions for given replacement values of the variables. Students will choose an appropriate computational technique, such as mental mathematics, calculator, or paper and pencil.

The instructional objective that the teacher has written for this learning standard is:

The teacher has been told that the class must meet standards this year, since the school did not reach the expected 80% pass rate on the end of the year exam last term.Using the given fact that the sum of the measures of the 3 angles of a triangle is 180 degrees, students will write an algebraic equation that will allow them to solve for the measure of an individual angle.