Video Transcript
Evaluate nine 𝑥 if 𝑥 equals one-fifth.
In this question, we are asked to evaluate an algebraic expression involving a
variable 𝑥 by using the fact that 𝑥 is equal to one-fifth. To do this, we substitute 𝑥 equals one-fifth into the expression, where we recall
that nine 𝑥 is shorthand for nine times 𝑥. This gives us nine multiplied by one-fifth.
We can then evaluate this expression by recalling that we can multiply a fraction by
an integer when multiplying the numerator of the fraction by the integer. This gives us nine times one over five. We know that nine times one is nine, so we obtain nine over five. Since nine and five share no common factors greater than one, we cannot simplify this
fraction. So, we can leave our answer as nine over five.
