有4絛數學唔識做

1. 3y－8y＋2y
= -3y(當冇y的存在,3-8+2)

2. (－3)－(－5)＋(－6)
= -3 + 5 - 6 (負負得正=+5, 正負得負=-6)
= -4

3. 5x－12=48
5x = 48+12
5x = 60
x = 60/5
x = 12

4.3(2x－5)=－6
6x - 15 = -6
6x = -6 +15
6x = 9
x = 9/6
x = 1.5

1.化簡 3y－8y＋2y
3y-8y+2y
=3-8+2(y)
=-3y
2.計算 (－3)－(－5)＋(－6)
(-3)-(-5)+(-6)
=-3+5-6
=-4
3.解方程 5x－12=48
5x-12=48
5x=60
x=12
4.解方程 3(2x－5)=－6
3(2x－5)=－6
6x-15=-6
6x =9
x=9/6
x=3/2
x=1.5

1. -3y

2.-3+5-6=-4

3.5x=60
x=12

4.6x-15=-6
6x=9
x=9/6
x=3/2

1.-3y
2.(-3)+5-6=-4
3.5x=48+12
x=60/5
x=12
4.6x-15=-6
6x=-6+15
x=9/6
x=3/2

1.化簡 3y－8y＋2y
= y(3-8+2)
= -3y

2.計算 (－3)－(－5)＋(－6)
= -3+5-6
= -4

3.解方程 5x－12=48
--> 5X = 48+12
--> 5X = 60
--> X = 60/5
--> X = 12

4.解方程 3(2x－5)=－6
--> 6X - 15 = -6
--> 6X = 15-6
--> 6X = 9
--> X = 9/6
--> X = 1.50

1. 3y-8y+2y
= -5y+2y
= -3y

2. (-3)-(-5)+(-6)
= -3 + 5 - 6
= 2-6
= -4

3. 5x - 12 = 48
5x=48 + 12
x=60 / 5
x=12

4. 3(2x-5) = -6
2x - 5 = -6/3
2x= -2+5
x= 3/2

註: 負負得正..正負得負..

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小朋友，學業要緊.. 如果問左咁多條都唔識做，過多幾個月點去考試呀?建議你找數學先生傾下..