Tristan invests $8100 in two different accounts. The first account paid 10%, the second account paid 11% in interest. At the end of the first year he had earned $842 in interest. How much was in each account?

Each side of the square = (4a - 3)

The dimensions of the rectangle are  (3a -5b) and (3a + 5b).

Step-by-step explanation:

Part - A

The area of the square is  

By ALGEBRAIC IDENTITY:

⇒

⇒ the Area of the square is

Also, AREA OF THE SQUARE =  

Hence, on comparing the two, side of the square = (4a - 2)

Part - B

The area of the rectangle is  

By ALGEBRAIC IDENTITY:

⇒

⇒ the Area of the rectangle is (3a -5b)(3a + 5b)

Also, AREA OF THE Rectangle  =  Length x Width

Hence, on comparing the two,

The dimensions of the rectangle are  (3a -5b) and (3a + 5b).