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Evaluating expressions in one variable

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The Evaluating expressions in one variable exercise appears under the 6th grade (U.S.) Math Mission and Algebra I Math Mission. This exercise helps in the basic understanding of Algebra.

Types of problems

  1. Evaluate the following expression when {x} = a number - This problem gives the user an expression with an unknown and a number added of subtracted to that unknown {x}. The user is to substitute the {x} value into the expression and evaluate it.


  1. It is not so easy to get the accuracy badges and speed badges in this exercise. Substituting the {x} into the expression and evaluating it may take some time.

Real-life Applications

  1. Work problems often ask us to calculate how long it will take different people working at different speeds to finish a task. The algebraic models of such situations often involve rational equations derived from the work formula, {W = rt}. The amount of work done ({W}) is the product of the rate of work ({r}) and the time spent working ({t}). The work formula has 3 versions:
    {W = rt}
    {t = \frac{W}{r}}
    {r = \frac{W}{t}}
  2. Knowledge of algebra is essential for higher math levels like trigonometry and calculus. Algebra also has countless applications in the real world.

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