The expression Joelle needs to use to tip her hairdresser is
[$@@MATH_TOKEN_0@@ ÷ 100], as per linear equation.
What is a linear equation?
A linear equation is an equation that contains one or more than one variable. In linear equation, the highest power of the variable is 1.
The amount for haircut is $38.
Joelle wants to tip 20% of her bill.
Therefore, the tip is
= $@@MATH_TOKEN_1@@ ÷ 100
= $7.6
Learn more about linear equation here: https://brainly.com/question/10675993
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