\(3x=7x\)

\(\Rightarrow3x-7x=0\)

\(x\left(3-7\right)=0\)

\(-4x=0\)

\(x=0\div\left(-4\right)\)

\(x=0\)

\(x\times11=66\)

\(x=66\div11\)

\(x=6\)

               3X = X x 7

                 X = 5

Vì : 35 = 5 x 7

                X x 11 = 66

                X          = 66 : 11

               X            =     6

                                      Chúc bạn học tốt nhé 

câu 1 mình ko bít câu 2 là X=66:11X=6

Bài 2:

\(a.\left(y+3,02\right):1,5=6,9\times0,3.\\ \Leftrightarrow\left(y+3,02\right):1,5=2,07.\\ \Leftrightarrow y+3,02=3,105.\\ \Leftrightarrow y=0,085.\)

\(b.16,15:\left(y\times19\right)=17.\\ \Leftrightarrow y\times19=0,95.\\ \Leftrightarrow y=0,05.\)

\(c.0,5\times y:5=10\times0,2.\\ \Leftrightarrow0,5\times y:5=2.\\ \Leftrightarrow0,5\times y=10.\\ \Leftrightarrow y=20.\)

Bài 1:

a) 7x + 3 = 24                                      b) 7x + 21 = 0

<=> 7x = 21                                         <=> 7x = -21

<=> x = 3                                             <=> x = -3

Vậy x \(\in\left\{3\right\}\)                                           Vậy x \(\in\left\{-3\right\}\)

c) 5 - 2x = 7

<=> 2x = -2

<=> x = -1

Vậy x \(\in\left\{-1\right\}\)

Bài 2:

a) \(\dfrac{2}{3}x-\dfrac{3}{2}x=\dfrac{5}{12}\)

<=> \(\dfrac{-5}{6}x=\dfrac{5}{12}< =>x=\dfrac{-1}{2}\)

Vậy x \(\in\left\{\dfrac{-1}{2}\right\}\)

b) \(\dfrac{-2}{3}x+\dfrac{1}{5}=\dfrac{3}{10}< =>\dfrac{-2}{3}x=\dfrac{1}{10}\)

<=> \(x=\dfrac{-3}{20}\)

Vậy x \(\in\left\{\dfrac{-3}{20}\right\}\)

c) \(\dfrac{2}{3}x-\dfrac{1}{2}=\dfrac{1}{10}< =>\dfrac{2}{3}x=\dfrac{3}{5}< =>x=\dfrac{9}{10}\)

Vậy x \(\in\left\{\dfrac{9}{10}\right\}\)

d) \(5\dfrac{4}{7}:x=13< =>\dfrac{39}{7}:x=13\)

<=> x = \(\dfrac{3}{7}\)

Vậy x \(\in\left\{\dfrac{3}{7}\right\}\)

Năn nỉ dữ quá :))

a) 7/15 + 4/5 

= 7/15 + 12/15

= 19/15

b) 1/16 : 11/16

= 1/16 x 16/11

= 1/11

a)=\(\frac{7}{15}\)+\(\frac{12}{15}\)=\(\frac{19}{15}\)

b)\(\frac{1}{16}\)x\(\frac{16}{11}\)=\(\frac{1x16}{16x11}\)=\(\frac{1}{11}\)

tk đi

a) 7/15+4/5=7/15+12/15=19/15

b)1/16:11/16=1/16*16/11=1/11

NHỚ H ĐẤY

M=8^10+4^10/8^4+4^11

=(2^3)^10+(2^2)^10/(2^3)^4+(2^2)^11

=2^30+2^20/2^12+2^22

=2^(30+20)/2^(12+22)

=2^50/2^34

=2^16

mik lm xog r nha

19:
AB=2*IA=4cm

20:

a: OA<OB

=>A nằm giữa O và B

b: A nằm giữa O và B

=>OA+AB=OB

=>AB=4cm

c: A nằm giữa O và B

AB=AO

=>A là trung điểm của BO

phải K nha ^^

Tham khảo:

I have just returned from a 1-week holiday with my friends in Da Nang and Quang Ngai. We stayed most of the time in Da Nang. Then we spent the last few nights in a very picturesque and historic place called Hoi An Old Town. We had such a relaxing time on our holiday. We enjoyed some wonderful local food. It’s really delicious. The activities we enjoyed on holiday were walking, swimming and go out at night. The water is so fresh and clean, and the temperature is just refreshing – not too hot and not too cold. We went hiking in the mountains nearly for some days, which was very good for our fitness. I really enjoyed this holiday. I loved the fresh air and the scenery, and of course the food. I will certainly be going back there another year, as I think it’s one of my favourite parts of the world.