The area of a rectangular painting is 13.02 square feet. the width is 4.2 feet. what is the length?

The length of the rectangle is 3.1 feet.

SOLUTION:

Given that, the area of a rectangular painting is 13.02 square feet.  The width is 4.2 feet.  

We have to find the length. Now, we know that, area of the rectangle is the product of its length and breadth i.e.

where l is the length of the rectangle and b is breadth of the rectangle.

Here, area = 13.02 square feet; b = 4.2 feet  

On substituting in the formula we get,

Hence, the length is 3.1 feet.

none of the above.

for one of the equations to be used in the process, there has to be a term in the equation since squared is .

since there is only a term in the first equation, we cannot derive a from completing the square.

solving with completing the square