1) 35 x 1001 - 35 = 35 x 1001 - 35 x 1

= 35 x (1001 - 1)

=35 x 1000

= 35 000

2) 140 x 14 x 5 - 14 x 3

= 14 x ( 140 x 5 - 3)

= 14 x 679

=9758

1) 35 x 1001 - 35

=  35 x (1001-1)

=  35 x 1000

=  35000

2) 140 x 14 x 5 - 14 x 3

=  (140 x 5) x 14 - 14 x 3

=   700 x 14 - 14 x 3

=    14 x (700-3)

=     9758

Ai k mik mik k lại

a ) 35 000

b ) 9758

Học sinh nhẩm và ghi kết quả như sau:

7 x 5 = 35

7 x 6 = 42

7 x 2 = 14

7 x 4 = 28

35 : 7 =5

42 : 7 = 6

14 : 7 = 2

28: 7 =4

35 : 5 = 7

42 : 6 = 7

14 : 2 = 7

28 : 4 = 7

2/3 = 2 x 4/ 3 x 4 =8/12

8/14 = 8 : 2/ 14 : 2 =4/7

5/9 = 5 x3/ 9 x 3 =15/37

35/ 40 = 35 : 5/ 40 : 5=7/8

a: \(x-43=\left(35-x\right)-48\)

=>\(x-43=35-x-48\)

=>\(x-43=-x-13\)

=>\(x+x=-13+43\)

=>2x=30

=>x=30/2=15

b: \(305-x+14=48+\left(x-23\right)\)

=>\(319-x=48+x-23=25+x\)

=>\(x+25=319-x\)

=>\(x+x=319-25\)

=>\(2x=294\)

=>\(x=\dfrac{294}{2}=147\)

c: \(-\left(-x-6+85\right)=\left(x+51\right)-54\)

=>\(-\left(-x+79\right)=x+51-54\)

=>x-79=x-3

=>-79=-3(vô lý)

=>\(x\in\varnothing\)

d: \(-\left(35-x\right)-\left(37-x\right)=33-x\)

=>\(-35+x-37+x=33-x\)

=>2x-72=-x+33

=>\(2x+x=33+72\)

=>3x=105

=>\(x=\dfrac{105}{3}=35\)

ĐK: \(x\ge-1\)

pt <=> \(\left(14\sqrt{x+35}-84\right)+\left(6\sqrt{x+1}-\sqrt{x^2+36x+35}\right)=0\)

<=> \(14\left(\sqrt{x+35}-6\right)+\sqrt{x+1}\left(6-\sqrt{x+35}\right)=0\)

<=> \(\left(\sqrt{x+35}-6\right)\left(11-\sqrt{x+1}\right)=0\)

<=> \(\orbr{\begin{cases}\sqrt{x+35}-6=0\\11-\sqrt{x+1}=0\end{cases}}\)Em làm tiếp nhé!

\(C.x=10\)

 C.x=10

C. x=10

a .   x   -   3 4   =   3 5 x   =   3 5   +   3 4 x = 27 20

b .   x   :   1 4 = 16 x = 16 x 1 4 x   =   4