Ghi kết quả tính:
17 − 4 − 3 = .....
17 − 7 = .....
10 − 3 − 5 = .....
10 − 8 = .....
10 − 2 − 3 = .....
10 − 5 = .....
BÀI 4: TÌM X (ghi rõ cách tính và kết quả)
1) 3x – 15 = 45
2) 35 – 5x = 50
3) (2x – 5) + 17 = 6
4) 10 – 2(4 – 3x) = -4
5) - 12 + 3(-x + 7) = -18
6) 24 : (3x – 2) = -3
7) -45 : 5.(-3 – 2x) = 3
1) 3x = 45 + 15 = 60
x = 60 : 3 = 20
2) 5x = 50 - 35 = 15
x = 15 : 5 = 3
3) (2x - 5) + 17 = 6
2x - 5 = 6 - 17
2x - 5 = -11
2x = -11 + 5
2x = -6
x = -6 : 2 = -3
4) 10 - 2(4 -3x) = -4
2(4 - 3x) = -4 - 10 = -14
4 - 3x = -14 : 2 = -7
3x = -7 - 4 = -18
x = -18 : 3 = -6
BÀI 4: TÌM X (ghi rõ cách tính và kết quả)
1) 3x – 15 = 45
2) 35 – 5x = 50
3) (2x – 5) + 17 = 6
4) 10 – 2(4 – 3x) = -4
5) - 12 + 3(-x + 7) = -18
6) 24 : (3x – 2) = -3
7) -45 : 5.(-3 – 2x) = 3
Tính hợp lí:
a) 10/17 - 5/13 - (-7)/17 - 8/13 + 11/25
b) 4/20 + (-16)/42 - 6/15 + 3/-5 + 2/21 + 3/20 + (-10)/21
( "/" là phần, tất cả các số hạng hoặc số bị trừ, số trừ đều là phân số)
GHI RỖ BƯỚC TRUNG GIAN, KHÔNG ĐƯỢC RA LUÔN KẾT QUẢ MÀ KHỒNG CÓ CÁC BƯỚC
Bạn nào nhanh mình tick :)
a) 10/17 - 5/13 -(-7)/17 - 8/13 + 11/25
=[10/17 + 7/17] - (5/13 + 3/13) + 11/25
=1-1+11/25 = 11/25
b) 4/20 + (-16)/42 - 6/15 + 3/-5 + 2/21 + 3/20 + (-10)/21
=(4/20+3/20) - (6/15+3/5) + (2/21+(-10)/21) + (-16)/42
=7/20 - 1 + (-8)/21 + (-16)/42
= -593/420
Tính:
a) -5/7(14/5 - 7/10) : |-2/3| - 3/4(8/9 + 16/3) + 10/3(1/3 + 1/5)
b) 17/-26(1/6 - 5/3) : 17/13 - 20/3(2/5 - 1/4) + 2/3(6/5 - 9/2)
c) -8/9(9/8 - 3/2) + 5/4 : (5/2 - 15/4) - 3/4(10/9 - 8/3) : (-1/3)
d) 21/10 : (12/5 - 9/10) . (-4/7) - 3/2(1/6 - 7/12) + 1/5(3/2 - 1/4)
a) Ta có: \(\dfrac{-5}{7}\left(\dfrac{14}{5}-\dfrac{7}{10}\right):\left|-\dfrac{2}{3}\right|-\dfrac{3}{4}\left(\dfrac{8}{9}+\dfrac{16}{3}\right)+\dfrac{10}{3}\left(\dfrac{1}{3}+\dfrac{1}{5}\right)\)
\(=\dfrac{-5}{7}\cdot\dfrac{3}{2}\cdot\dfrac{21}{10}-\dfrac{3}{4}\cdot\dfrac{56}{3}+\dfrac{10}{3}\cdot\dfrac{8}{15}\)
\(=\dfrac{-9}{4}-14+\dfrac{16}{9}\)
\(=\dfrac{-1621}{126}\)
b) Ta có: \(\dfrac{17}{-26}\cdot\left(\dfrac{1}{6}-\dfrac{5}{3}\right):\dfrac{17}{13}-\dfrac{20}{3}\left(\dfrac{2}{5}-\dfrac{1}{4}\right)+\dfrac{2}{3}\left(\dfrac{6}{5}-\dfrac{9}{2}\right)\)
\(=\dfrac{-17}{26}\cdot\dfrac{13}{17}\cdot\dfrac{-3}{2}-\dfrac{20}{3}\cdot\dfrac{3}{20}+\dfrac{2}{3}\cdot\dfrac{-33}{10}\)
\(=\dfrac{3}{4}-1-\dfrac{11}{5}\)
\(=-\dfrac{49}{20}\)
Bài 1 : Tính nhanh , bỏ ngoặc rồi tính
a) ( 135 - 35 ) . ( - 37 ) + 37 . ( - 42 - 58 )
b) - 65 . ( 87 - 17 ) - 87 . ( 17 - 65 )
c) [ 3 . ( - 2 ) - ( - 8 ) ] . ( - 7 ) - ( - 2 ) . ( - 5 )
Bài 2 : Tính nhanh giá trị biểu thức
a) ( - 55 ) . ( - 25 ) . ( - 8 )
b) ( - 1 ) . ( -2 ) . ( - 3 ) . ( - 4 ) . ( - 5 ) . 10
Các bạn nhớ ghi đầy đủ các bước làm đừng ghi mỗi kết quả thôi nhé .
Answer:
Bài 1:
\(\left(135-35\right).\left(-37\right)+37.\left(-42-58\right)\)
\(=100.\left(-37\right)+37.\left(-100\right)\)
\(=\left(-3700\right)+\left(-3700\right)\)
\(=-7400\)
\(-65.\left(87-17\right)-87.\left(17-65\right)\)
\(=\left(-65\right).87-\left(-65\right).17-87.17+87.65\)
\(=-\left(-65\right).17-87.17\)
\(=17.\left(65-87\right)\)
\(=-374\)
\([3.\left(-2\right)-\left(-8\right)].\left(-7\right)-\left(-2\right).\left(-5\right)\)
\(=[\left(-6\right)+8].\left(-7\right)-\left(-2\right).\left(-5\right)\)
\(=2.\left(-7\right)-10\)
\(=-24\)
Bài 2:
\(\left(-55\right).\left(-25\right).\left(-8\right)\)
\(=\left(-55\right).[\left(-25\right).\left(-8\right)]\)
\(=\left(-55\right).200\)
\(=-11000\)
\(\left(-1\right).\left(-2\right).\left(-3\right).\left(-4\right).\left(-5\right).10\)
\(=[\left(-1\right).10].[\left(-2\right).\left(-5\right)].[\left(-3\right).\left(-4\right)]\)
\(=\left(-10\right).10.12\)
\(=-1200\)
Tính:
1, 7/36- 8/-9 + -2/3
2, -1/2 + 3/7 - 1/9 + -7/18 + 4/7
3, -10/3 + 13/10 - 1/6 + 1/10
4, 10/17- 5/13 - (-7/17) - 8/13 + 11/25
\(1.\) \(\dfrac{7}{36}-\dfrac{8}{-9}+\dfrac{-2}{3}=\dfrac{7}{36}+\dfrac{8}{9}-\dfrac{2}{3}=\dfrac{7+32-24}{36}=\dfrac{5}{12}.\)
\(2.\) \(\dfrac{-1}{2}+\dfrac{3}{7}-\dfrac{1}{9}+\dfrac{-7}{18}+\dfrac{4}{7}=\dfrac{-9-2-7}{18}+\dfrac{4+3}{7}=\dfrac{-18}{18}+\dfrac{7}{7}=-1+1=0.\)
\(3.\) \(-\dfrac{10}{3}+\dfrac{13}{10}-\dfrac{1}{6}+\dfrac{1}{10}=\dfrac{13+1}{10}+\dfrac{-20-1}{6}=\dfrac{14}{10}+\dfrac{-21}{6}=\dfrac{7}{5}-\dfrac{7}{2}=-\dfrac{21}{10}.\)
\(4.\) \(\dfrac{10}{17}-\dfrac{5}{13}-\left(-\dfrac{7}{17}\right)-\dfrac{8}{13}+\dfrac{11}{25}=\dfrac{10+7}{17}+\dfrac{-5-8}{13}+\dfrac{11}{25}=\dfrac{17}{17}-\dfrac{13}{13}+\dfrac{11}{25}=\dfrac{11}{25}.\)
Tính:
1, 7/36- 8/-9 + -2/3
2, -1/2 + 3/7 - 1/9 + -7/18 + 4/7
3, -10/3 + 13/10 - 1/6 + 1/10
4, 10/17- 5/13 - (-7/17) - 8/13 + 11/25
1: \(=\dfrac{7}{36}+\dfrac{32}{36}+\dfrac{-24}{36}=\dfrac{15}{36}=\dfrac{5}{12}\)
2: \(=\left(-\dfrac{1}{2}-\dfrac{1}{9}-\dfrac{7}{18}\right)+\dfrac{3}{7}+\dfrac{4}{7}\)
\(=\dfrac{-9-2-7}{18}+1=-1+1=0\)
3: \(=\left(-\dfrac{10}{3}-\dfrac{1}{6}\right)+\dfrac{14}{10}\)
\(=-\dfrac{21}{6}+\dfrac{14}{10}=\dfrac{-7}{2}+\dfrac{14}{10}=\dfrac{-35+14}{10}=-\dfrac{21}{10}\)
4: \(=\left(\dfrac{10}{17}+\dfrac{7}{17}\right)-\left(\dfrac{5}{13}+\dfrac{8}{13}\right)+\dfrac{11}{25}=\dfrac{11}{25}\)
Bài 1:Điền dấu thích hợp vào chỗ trống_:
a,(-15).(10-12)=[(-15)._-(-15)._ ]=_
b,(-17).10-(-3).10=[-17-(-3)]._=_
c,(-5).(-4)+(-5).14=(-5).14=(-5).[(-4)+_ ]=_
d,13.( _+8)=13.(-3)+13. _ =65
Mình cần gấp,mong mọi người có thể trả lời kết quả nhanh ạ.
a) \(\left(-15\right)\cdot\left(10-12\right)=\left[\left(-15\right)\cdot10-\left(-15\right)\cdot12\right]=-150+180=30\)
b) \(\left(-17\right)\cdot10-\left(-3\right)\cdot10=\left[-17-\left(-3\right)\right]\cdot10=\left(-17+3\right)\cdot10=-14\cdot10=-140\)
(13/-10 - -4/13)+11/10 A=-5/9+8/15+ -2/11 + 4/-9 + 7/15 B=10/17-5/13- -7/17 - 8/13+11/25 (3/4-1/6):2/3 (31/10-5/2).3-2 Giải chi tiết giúp bngoc ạ cmon trước💖
a: =-5/9-4/9+8/15+7/15-2/11=-2/11
b: =10/17+7/17-5/13-8/13+11/25
=11/25
c: =(9/12-2/12)*3/2=7/12*3/2=21/24=7/8
d: =(31/10-25/10)*3-2
=3/5*3-2
=9/5-2
=-1/5