Answer:
8. 10 ft^2
9. 64 km^2
10. 245 m^2
Explanation:
8.
the square on the right is 1x1 thus has an area of 1
the center rectangle is 2x3 thus has an area of 6
the triangle on the left is 2x3/2 thus has an are of 3
9.
the squares are identical so the area of one of the x2 will get you the answer
8x4x2=64
10.
10x7=70
9x14=126
7x14/2=49
70+126+49=245