2. 解下列方程。
$8x÷6 = 0.48$
$12x - 5x = 8.4$
$4.8÷0.8x = 3$
$2.4×4 - 2.9x = 3.8$
$7.6×5 - 7x = 10$
$6.12×0.5 + 0.6x = 7.2$

2.
$8x ÷ 6 = 0.48$
解：$8x = 0.48 × 6$
$8x = 2.88$
$x = 2.88 ÷ 8$
$x = 0.36$
$12x - 5x = 8.4$
解：$7x = 8.4$
$x = 8.4 ÷ 7$
$x = 1.2$
$4.8 ÷ 0.8x = 3$
解：$0.8x = 4.8 ÷ 3$
$0.8x = 1.6$
$x = 1.6 ÷ 0.8$
$x = 2$
$2.4 × 4 - 2.9x = 3.8$
解：$9.6 - 2.9x = 3.8$
$2.9x = 9.6 - 3.8$
$2.9x = 5.8$
$x = 5.8 ÷ 2.9$
$x = 2$
$7.6 × 5 - 7x = 10$
解：$38 - 7x = 10$
$7x = 38 - 10$
$7x = 28$
$x = 28 ÷ 7$
$x = 4$
$6.12 × 0.5 + 0.6x = 7.2$
解：$3.06 + 0.6x = 7.2$
$0.6x = 7.2 - 3.06$
$0.6x = 4.14$
$x = 4.14 ÷ 0.6$
$x = 6.9$

3. 看图列方程并求解。
(1)$S = 8.4$平方厘米

(2)$S = 24.8$平方厘米

(3)$S = 20$平方厘米

(4)

(1) (2.5+3.5)x÷2=8.4
解：6x÷2=8.4
3x=8.4
x=2.8
(2) 8x=24.8
解：x=24.8÷8
x=3.1
(3) 8x÷2=20
解：4x=20
x=5
(4) 5x÷2=4×3÷2
解：5x÷2=6
5x=12
x=2.4