In algebra, letters are used when numbers are not known. Algebraic terms, such as \(2s\) or \(8y\), leave the multiplication signs out. So rather than \(2 \times s\), write \(2s\), and rather than \(8 ...

In algebra, letters are used to stand for values that can change (variables) or for values that are not known (unknowns). A term is a number or letter on its own, or numbers and letters multiplied ...

Students are introduced to Professor Arbegla and her amazing machine. They suggest numbers (and later geometric shapes) to go into the machine, and then analyze what comes out. Students learn to look ...