Question

giúp tôi làm bài này nhé 
-7( 5 - x) - 2( x - 10) = 15

Answer 1

\(-7\left(5-x\right)-2\left(x-10\right)=15\)

\(\Leftrightarrow-35+7x-2x+20=15\)

\(\Leftrightarrow7x-2x=15-20+35\)

\(\Leftrightarrow5x=30\)

\(\Leftrightarrow x=6\)

...

Answer 2

chép mạng là xong

Answer 3

-7( 5 - x) - 2( x - 10) = 15

−35+7x−2x+20=15

−15+5x=15

5x−15=15

5x=15+15

5x=30

x=30:5

x=6

Answer 4

\(-7\left(5-x\right)-2\left(x-10\right)=15\)5

\(\Leftrightarrow-35+7x-2x+20=15\leftrightarrow\)\(5x-15=15\)

\(\Leftrightarrow5x=30\)

\(\Leftrightarrow x=6\)