Given,
The area of the front yard is 60x^2 + 12x - 21 .
The grass area of the backyard is 81x^2 - 212x + 68.
The total are is the sum of the front yard and the back yard.
So, to obtain the total area adding the area of the front yard and back yard.
Hence, the total area is 141x^2-200x+47.