Khoa j =))

​

\(\left(x+3\right)\left(x+4\right)\left(x+5\right)\left(x+6\right)=0\)

TH1: \(x+3=0\Rightarrow x=-3\)

TH2: \(x+4=0\Rightarrow x=-4\)

TH3: \(x+5=0\Rightarrow x=-5\)

TH4: \(x+6=0\Rightarrow x=-6\)

Vậy: \(x=-3\) hoặc \(x=-4\) hoặc \(x=-5\) hoặc \(x=-6\)

\(\frac{x}{2}=\frac{y}{3}=\frac{z}{7}\) và \(x+2y+3z=58\)

Áp dụng tính chất của dãy tỉ số bằng nhau, ta có:

\(\frac{x}{2}=\frac{y}{3}=\frac{z}{7}=\frac{x+2y+3z}{2+6+21}=\frac{58}{29}=2\)

=> \(x=2.2=4\)

\(y=2.3=6\)

\(z=2.7=14\)

Vậy: \(x=4\)

\(y=6\)

 \(z=14\)

4568,2 triệu năm

\(\frac{3}{7}.\left(7x+\frac{2}{3}\right)-2\left(\frac{5}{14}-3x\right)=\frac{15}{5}\)

<=> \(\left(3x+\frac{2}{7}\right)-\left(\frac{5}{7}-6x\right)=\frac{15}{5}\)

<=> \(3x+\frac{2}{7}-\frac{5}{7}+6x=\frac{15}{5}\)

<=> \(9x-\frac{3}{7}=3\)

<=> \(9x=\frac{24}{7}\)

<=> \(x=\frac{24}{7}.\frac{1}{9}=\frac{8}{21}\)

C1: \(3^{4000}=3^{4000}\)

\(9^{2000}=\left(3^2\right)^{2000}=3^{4000}\)

Vì: \(3^{4000}=3^{4000}\) => \(3^{4000}=9^{2000}\)

C2: \(3^{4000}=\left(3^4\right)^{1000}=81^{1000}\)

\(9^{2000}=\left(9^2\right)^{1000}=81^{1000}\)

Vì: \(81^{1000}=81^{1000}\) => \(3^{4000}=9^{2000}\)

10% của 8 là:                                 
8 x 10% = 0,8

o to khoi hanh luc la

doi 45 phut = 0,75 gio

7 + 0,75 = 7,75 gio = 7 gio 45 phut

nho cho **** nhe

sắp xếp lại cho đúng

a is Lan'  garden there big house behind

=> There is a big house behind Lan's garden.

an city the apartment in we in live

=> We live in an anpartment in the city.

uncle in country does work your the 

=> Does your uncle work in the country?

goes father bus work her by to

=> Her father goes to work by bus.

time leave the what morning mr ba does house in his

=> What time does Mr.Ba leave his house in the morning?

any street there our aren't on trees

=> There aren't any trees on our street.

city is brother phong with the his in

=> Phong is in the city with his brother.

front a house there of garden her is vegetable

=> There is a vegetable garden in front of her house.

ho chi minh city mrs oanh do my family to how and travel her

=> How do Mrs.Oanh and her family travel to Ho Chi Minh city?