p = 2l + 2w = 35...If Jim and his dad decide to decrease the width of the flower bed from 15 feet, what happens to its length?

Question

p = 2l + 2w = 35...If Jim and his dad decide to decrease the width of the flower bed from 15 feet, what happens to its length?

Answer 1

The perimeter is 35.  If we were to change the width, which is one of the dimensions of the flower bed, The perimeter will change.  This means that perimeter will no longer be 35.  So in order to keep the perimeter as it is, if we change one dimension, we must also change the other.

 

Let's solve for the length, using the formula to see how much the length changes from.

 

p = 2l + 2w

 

35 = 2l + 2(15)

 

35 = 2l + 30

 

5 = 2l

 

2.5 = l

 

 

We must increase the length from 2.5 feet.  This is because decreasing one dimension will decrease the perimeter.  But if we increase the other dimension as well, it will restore the perimeter to where is was initially.

Answer 2

Assuming they want the perimeter to remain at 35,

If the width is decreased by 15 feet the perimeter is decreased by 30 feet - there are 2 widths.

Therefore the length has to be increased by 15 feet - there are two lengths.