Question

A rectangular turtle aquarium is 6 ft long by 4 ft wide. The aquarium is enlarged by increasing

the length and width by an equal amount in order to double its area. What are the dimensions of
the new aquarium?

Answer 1

8ft x 6ft

Explanation:

For this problem, we want to create measurements of length and width that double our current area. First we need to find the current area.

C_Length = 6 ft

C_Width = 4 ft

C_Area = C_Length * C_Width

C_Area = 6 ft * 4 ft = 24 ft^2

Now we want our new area to be double the old area.

N_Area = 2C_Area

N_Area = 2 * 24 ft^2

N_Area = 48 ft^2

Now we simply need to find the increase in width and length, distributed equally, that will create the new area.

N_Area = (C_Length + x) * (C_Width + x)

Where x is the amount that each variable is increased by to create the new area.

Now we simply solve for x.

N_Area = (C_Length + x) * (C_Width + x)

48 = (6 + x) * (4 + x)

48 = 24 + 10x + x^2

0 = -24 + 10x + x^2

Now we can either apply the quadratic formula or attempt to factor using the constant break down method.

(x + 12) (x - 2) = 0

x = -12; x = 2

Note that we will choose x = 2 since the other option would require us to have negative material, which is impossible.

Now we can check to validate our answer by plugging in the value of x.

48 ?= (6 + 2) * (4 + 2)

48 ?= (8) * (6)

48 == 48

Thus, we have found the dimensions of the new aquarium, 8ft x 6ft.

Cheers.