Jawaban:

7x+5y

Luas tanah seleuruhnya dalam bentuk aljabar adalah begin mathsize 14px style open parentheses 10 minus x close parentheses squared equals 100 minus 20 x plus x squared end style

Luas tanah untuk kolam ikan dalam bentuk aljabar adalah begin mathsize 14px style left parenthesis 8 minus x right parenthesis end style to the power of size 14px 2 size 14px equals size 14px 64 size 14px minus size 14px 16 size 14px x size 14px plus size 14px x to the power of size 14px 2

Luas tanah seluruhnya adalah size 14px 100 size 14px minus size 14px 20 size 14px x size 14px plus size 14px x to the power of size 14px 2 size 14px equals size 14px 64 size 14px minus size 14px 16 size 14px x size 14px plus size 14px x to the power of size 14px 2 size 14px plus size 14px 28 size 14px 100 size 14px minus size 14px 20 size 14px x size 14px plus size 14px x to the power of size 14px 2 size 14px equals size 14px 92 size 14px minus size 14px 16 size 14px x size 14px plus size 14px x to the power of size 14px 2 size 14px 100 size 14px minus size 14px 92 size 14px equals size 14px minus size 14px 16 size 14px x size 14px plus size 14px 20 size 14px x size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px 8 size 14px equals size 14px 4 size 14px x size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px space size 14px 2 size 14px equals size 14px x

Sehingga luas sebenarnya adalah begin mathsize 14px style 100 minus 20 x plus x squared equals 100 minus 20 left parenthesis 2 right parenthesis plus 2 squared space space space space space space space space space space space space space space space space space space space space space space equals 64 end style