giúp diii

Giúp vs mn ơi mik cần gấp ạ

b) -2x² - 10x

c) -x² + 3x

d) x^2 - 9x + 18

a) \(\dfrac{x-1}{x+5}=\dfrac{6}{7}\left(đk:x\ne-5\right)\)

\(\Rightarrow7\left(x-1\right)=6\left(x+5\right)\)

\(\Rightarrow x=37\left(tm\right)\)

b) \(\dfrac{x^2}{6}=\dfrac{24}{49}\)

\(\Rightarrow x^2=\dfrac{24.6}{49}=\dfrac{144}{49}\)

\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{12}{7}\\x=-\dfrac{12}{7}\end{matrix}\right.\)

C. 1. - How long does it take you to go from your house to the nearest open-air market?

- It takes me 5 minutes.

2. - How long does it take you to go from your school to the playground?

- It takes us 2 minutes. 

D. 3. - How long does it take you to go from your house to the river?

- It takes me half an hour (30 minutes).

4. How long does it take you to go from the bus station to your village?

- It takes me an hour and 15 minutes. 

1D 2A 3C 4D 5B 6C 7B 8D 9B 10C 11B 12D 13A 14C 15C 16B 17C 18A 19B 20C