幾題數中一(要2-3個步驟就得啦)10分

1. [(+3)-(-4)(-5)]÷[(-4)(-3)]
=[+3-(+20)]÷[+12]
=[+3-20]÷[+12]
=[-17]÷[+12]
= -17/12

2. [(-2)(+3)-(-2+3)]÷[(+2)(-3)]
=[(-6)-(+1)]÷[-6]
=[(-6)-1]÷[-6]
=[-7]÷[-6]
= 7/6

3. [(-13)-(+2)]÷[(+2)-(-1)]
=[(-13)-2]÷[(+2)+1]
=[-15]÷[+3]
= -5

4. [(+100)÷(-5)]÷[(-2)+(+1)]
=[-20]÷[(-2)+1]
=[-20]÷[-1]
= 20


　 2　　　2
5. -3x(-4)-(-2)
=(+9)x(-4)-(+4)
=(-36)-(+4)
=(-36)-4
= -40

　　　　 2　 2
6. (-6)+(-1)x(-5)
=(-6)+(+1)x(+25)
=(-6)+(+25)
=(-6)+25
= 19

1. [(+3)-(-4)(-5)]÷[(-4)(-3)]
= [(+3)-(+20)]÷[+12]
= [-17]÷[+12]
= -17/12

2. [(-2)(+3)-(-2+3)]÷[(+2)(-3)]
= [(-6)-(+1)]÷[-6]
= [-7]÷[-6]
= 7/6
= 1 1/6

3. [(-13)-(+2)]÷[(+2)-(-1)]
= [-15]÷[+3]
= -15/3
= -5

4. [(+100)÷(-5)]÷[(-2)+(+1)]
= [-20]÷[-1]
= 20

　 2　　　2
5. -3x(-4)-(-2)
= 9x(-4)-(4)
= -36-4
= -40

　　　　 2　 2
6. (-6)+(-1)x(-5)
= (-6)+(1)x(25)
= (-6)+25
= 19

1.
[(+3)-(-4)(-5)]÷[(-4)(-3)]
= (3-20)÷12
= -17/12

2.
[(-2)(+3)-(-2+3)]÷[(+2)(-3)]
=(-6-1)÷(-6)
=7/6

3.
[(-13)-(+2)]÷[(+2)-(-1)]
=(-13-2)÷(2+1)
= -15÷3 = -5

4.
[(+100)÷(-5)]÷[(-2)+(+1)]
= -20÷ (-1) = 20

　 2　　　2
5. -3x(-4)-(-2)
=9x(-4)-4
= -40

　　　　 2　 2
6. (-6)+(-1)x(-5)
=(-6)+1x25
=19

1. [(+3)-(-4)(-5)]÷[(-4)(-3)]
=(-17)/(12)//

2. [(-2)(+3)-(-2+3)]÷[(+2)(-3)]
=(-7)/(-6)
=7/6//

3. [(-13)-(+2)]÷[(+2)-(-1)]
=(-15)/(3)
=-5//

4. [(+100)÷(-5)]÷[(-2)+(+1)]
=(-20)/(-1)
=20//