17. You are supposed to use the perimeter formula for a rectangle. Your text has apparently written that formula as
.. P = 2w +2l
You are given values for P and l. Put them in the formula.
.. 6 = 2w +2*1
Solve in the usual way. First, subtract 2.
.. 4 = 2w
Then, divide by 2
.. 2 = w
You have found w, and it is 2.
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Personally, I like to write the perimeter formula for a rectangle as
.. P = 2(w +l)
Usng this version, we can fill in values and get
.. 6 = 2(w +1)
Dividing by 2 gives
.. 3 = w +1
Subtracting 1, we get
.. 2 = w