An equation that can be used to solve for how long it took Piper to walk from the park to the store will be x + 2x = 21.
What is equation?
In its simplest form in algebra, the definition of an equation is a mathematical statement that shows that two mathematical expressions are equal. For instance, 3x + 5 = 14 is an equation, in which 3x + 5 and 14 are two expressions separated by an 'equal' sign.
Piper skated 2 times long, so it gives us the first clue to 2x.
And also, they said the total time spent walking and skating was 21 minutes. And we would also know that the x will be from Piper skated 2 times long so, we know that the x will go first.
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