Fandom

Khan Academy Wiki

Evaluating expressions in one variable

1,860pages on
this wiki
Add New Page
Talk0 Share

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

Screenshot01
  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.

Strategies

  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.

Ad blocker interference detected!


Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.