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The Evaluate expressions with unknown variables (basic) exercise appears under the Algebra I Math Mission and Mathematics II Math Mission. This exercise practices substituting into expressions for several variables simultaneously.

Types of Problems[]

There is one type of problem in this exercise:

  1. Evaluate the expression: This problem provides an equation (possibly two) with several variables and an expression involving those variables. The student is asked to find the value of the expression and write it in the space provided.
    Evaluate expressions with unknown variables (basic)

    Evaluate the expression

Strategies[]

An ability to visualize the expression and how it looks when distributed would assist with completing this exercise accurately and efficiently.

  1. On this exercise the coefficients on the equations are the same. Therefore the value of the instance of the variable in the expression is the coefficient times the value in the equation.
  2. On paper, the step-by-step process would be to factor a GCF out of the expression where appropriate, then substitute the value of the equation for it.

Real-life Applications[]

  1. Strategies like the ones needed for this exercise are common on standardizes tests and some math competitions such as AMC and AIME.
  2. Knowledge of algebra is essential for higher math levels like trigonometry and calculus. Algebra also has countless applications in the real world.