Answer:
#1: 11 cm
#2: 16.5 in
#3: 2.5 feet
Step-by-step explanation:
#1
Solve for width by substracting 2l on both sides to isolate 2w

or

Replace.

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#2


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#3

Solve for l

Since the graph is a linear function, we're going to use the slope formula solve this:
Note I am replacing m with k

Inserting 2 points from the graph, let's use (1,8) and (2,16).

k=8
C adding a number to itself
If you tell me the concepts you’re referring to I might be able to help