To convert 7km^2, 8m^2, and 9cm^2 to m^2, we need to convert each unit to meters and then add them together.

1 km = 1000 m
7 km^2 = 7 * (1000 m)^2 = 7 * 1000^2 m^2 = 7 * 1000000 m^2 = 7000000 m^2

1 cm = 0.01 m
9 cm^2 = 9 * (0.01 m)^2 = 9 * 0.0001 m^2 = 0.0009 m^2

Now we can add the areas together:
7000000 m^2 + 8 m^2 + 0.0009 m^2 = 7000008.0009 m^2

Therefore, 7km^2, 8m^2, and 9cm^2 is equal to 7000008.0009 m^2.