The perimeter of a rectangular building is 1200 feet. The width of the building is 2 feet less than three times the length. What is the width of the building?

Given:

The perimeter of a rectangular building is 1200 feet.

The width of the building is 2 feet less than three times the length.

To find:

Width of the building.

Solution:

Let length of the building be x.

Then, width = 3x-2

We know that,

Add 4 on both sides

Divide both sides by 8.

Now,

Therefore, the  width of the building is 449.5 feet.

robert puts 2 in each row

x^2 + 81

we can factor this using difference of square binomials.

rewrite the equation:

x^2 - (-81)

factor:

(a^2 - b^2) = (√a^2 + √b^2)(√a^2 - √b^2)

(x^2 - (-81) = (x + √-81)(x - √-81)

we can remove the - from under the radical by multiplying it by i.

(x^2 - (-81) = (x + i√81)(x - i√81)

(x^2 - (-81) = (x + 9i)(x - 9i)

we can check our answer by using foil:

x^2 - 9ix + 9ix - 81i^2

x^2 - 81^2

i^2 = -1

x^2 + 81