STEM Lessons for College Students

Beginning algebra: writing equations for word problems

We look at four different word problems and write an equation for each. The first one involves the perimeter of a parallelogram. The second, area of a two-part rectangle. The third one has to do with the ages of two people – we know one is four times as old as the other, and 40 years older than the other. In the last problem, we’re given the aspect ratio and the perimeter of a rectangle, and the task is to find the side lengths.

For each problem, write a fairly simple linear equation and then solve the equation. I also solve some problems without the equation first – so you can see how the mental math or bar diagram solution steps match with the steps of solving the equation.

This lesson is meant for pre-algebra or for beginning algebra students.

See also my other pre-algebra videos at

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