Question

A rectangle has a diagonal of 15cm and a width of 9cm. Find its length.explain how to do it please im really confused

Answer 1

Given :

A rectangle has a diagonal of 15cm and a width of 9cm

The diagonal represents a hypotenuse

See the following figure:

Using the Pythagorean to find length

diagonal = d = 15 cm

width = w = 9 cm

Length = l

So,

`l^2+w^2=d^2`
`\begin{gathered} l^2+9^2=15^2 \\ l^2+81=225 \\ l^2=225-81=144 \\ \\ l=\sqrt[]{144}=12 \end{gathered}`

So, the length of the rectangle = 12 cm