Write an expression for the length of an open polyline ABCD, if AB = m

Write an expression for the length of an open polyline ABCD, if AB = m m, BC is 5.37 cm more than AB, and CD is 4.89 dm less than AB, and simplify it.

Let some side of an open broken line ABCD have length AB = m meters, then:

m + 0.0537 (m) – the length of the aircraft link, since BC is 5.37 cm = 0.0537 m more than AB;

m – 0.489 (m) – the length of the CD link, since CD is 4.89 dm = 0.489 m less than AB.

Knowing that the length of an open polyline ABCD is equal to the sum of the lengths of all its three links, we compose an expression to determine its length:

AB + BC + CD = m + (m + 0.0537) + (m – 0.489) (m);

AB + BC + CD = 3 ∙ m – 0.4353 (m).

Answer: (m – 0.489) meters is the length of an open polyline ABCD.