Question

Question #70458

Answer 1

`b = "28 m"`

Explanation:

Let `a` be the height of the movie screen and `b` the width.

Then, the perimeter of the rectangle is

`P=2(a+b)`

The perimeter is `"80 m"`, so

`80=2(a+b)`

`40=a+b`

But the height is `"12 m"`, so

`40=12+b`

`b=28`