length comic strips

involving lengths as unknowns can be a helpful diagrammatic device for forming equations

in this case with the unknown on both sides

find the two original lengths, 'a' and 'b'

for question 1,
a + 2 = 2(b - 2)
so, a = 2b - 6
and
a - 1 = b + 1
so, a = b + 2

2b - 6 = b + 2

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