Question

Answer 1

\(\dfrac{AB}{CD}=\dfrac{5}{4}\\ =>\dfrac{AB}{20}=\dfrac{5}{4}\\ =>AB=25\left(cm\right)\)

Answer 2

`(AB)/(CD) = 5/4`

`=> (AB)/20 = 5/4`

`=> AB = 25cm`

Answer 3

\(\text{Ta có:}\dfrac{AB}{CD}=\dfrac{5}{4}\left(gt\right)\)

\(\text{Mà CD=20cm(gt)}\)

\(\Rightarrow\dfrac{AB}{20}=\dfrac{5}{4}\Rightarrow AB=\dfrac{20.5}{4}=25\left(cm\right)\)