Sanjay needs 90 meters of fence to go around a rectangular garden.
the length l of the garden is three times its width w.

three of these equations give the correct value for w.
which equation does not?

Option A is incorrect.

Step-by-step explanation:

Length of the given parts is l and width is w meters.

It is given in the question that Sanjay needs 90 meters of fence to go around the rectangular park.

It means perimeter of the park is 90 meters.

Since perimeter of a rectangle = 2(length + width)

                                                  =  2(L + w)

It is given that length of garden is three times of width so l = 300

therefore, equation will be

Perimeter = 2[3w + w]

           90 =  2[3w + w]

Option A ⇒ w + 3w = 90   ⇒ incorrect

Option B ⇒ w + 3w + w + 3w = 90

                   2(w + 3w) = 90  ⇒ Correct option

Option C ⇒ 2w + 2 (3w) = 90

                  2 [w + 3w] = 90   ⇒ Correct option

Option D ⇒ 2(3w + w) = 90  ⇒ Correct option

therefore Option A is incorrect option.

step-by-step explanation: