1. 直接写出得数。(20☆)
$7a + 3a = $
$1.5×3b = $
$1.4m - 0.6m = $
$2.4y - 1.5y = $
$19x - 3x = $
$a×(4 - a) = $
$4.1a - 2.7a = $
$y + 4y = $
$7.8x - 5x = $
$3×a = $
$16.6n - 0.6n = $
$3x + 5x = $
$4.3a + 4a = $
$1×c = $
$4×a + 6×a = $
$7a + a = $
$2y + 5.8y = $
$a×b×3 = $
$b×4 = $
$6y - y = $
$x + 1.2x = $
$7.7×0.1n = $
$5×7 - n = $
$7m - 3m = $
$2a + a = $
$5x + 16x = $
$1.5a×b = $
$21t - 9t = $
$0.55a + 0.45a = $
$a×4a = $
$2.6x - 1.4x = $
$12a - 4a = $
$b - 0.4b = $
$8b - 3b = $
$6b + 2.3b = $
$13b + b = $
$3.7x - 2.3x = $
$6.9n - 3.4n = $
$5c - 4c = $
$2×(30 - a) = $

10a 4.5b 0.8m 0.9y
16x 4a - a² 1.4a 5y
2.8x 3a 16n 8x
8.3a c 10a 8a
7.8y 3ab 4b 5y
2.2x 0.77n 35 - n 4m
3a 21x 1.5ab 12t
a 4a² 1.2x 8a
0.6b 5b 8.3b 14b
1.4x 3.5n c 60 - 2a

2. 解下列方程并检验。(18☆)
$x - 2.4 = 0.32$
$5 + x = 8.5$
$x - 8.4 = 14.3$
$x + 4.6 = 14.3$
$16.6 + x = 23.42$
$x - 12.3 = 153.7$

x = 2.72 x = 3.5 x = 22.7
x = 9.7 x = 6.82 x = 166

3. 看图列方程,并求出方程的解。(12☆)

x + 45 = 128 x = 83
x + 20 = 200 + 200 x = 380