To get the value of an expression you add

When we substitute a specific valuefor each variable, and then perform the operations, it's called evaluating theexpression. Let's evaluate theexpression 3y + 2y when 5 = y. Click on the steps to see how it's done. Perform the operations, to find the value of the expression.

Algebra Basics - Evaluating expressions - First Glance. We have learned that, in in an algebraic expression, letters can stand for numbers. When we substitute a specific value for each variable, and then perform the operations, it's called evaluating the expression.  For more go to

www.math.com/school/subject2/lessons/S2U2L3GL.html

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