2x - 5.5 × 6 = 3 3 × 1.5 + 4x = 7.5

Solution: 2x-33 = 3 Solution: 4.5+4x =7.5

2x= 3 + 33 4x = 7.5 - 4.5

2x = 36 4x = 3

x = 36 ÷ 2 x = 3 ÷ 4

x = 18 x = 0.75

Second, column calculation.

1. 12.4 × 0.6 = 7.44 2. 1.2 + 3.6 = 4.8

2.88 ÷ 4 = 0.72 3.6 ÷ 1.2 = 3

7.44 - 0.72 = 6.72 4.8 - 3 = 1.8

0.8 × 1.8 = 1.44

Three. 20-6 = 14 (m)

160 ÷ 20 = 8 (m)

( 14 +20)× 8 ÷ 2

= 34 × 8 ÷ 2

= 272 ÷ 2

= 136 (m2)

A: The shadow area is136m2.

P9 I didn't confirm it, so I didn't write it. I hope the above answers are helpful to everyone.