Question

HÃY tìm số N x:

(x-1)+10=7

(x+2)-6=10

Answer 1

(x-1)+10=7

x-1 =10-7

x-1 =3

=> x =3+1

=> x =4

(x+2)-6=10

x+2 =10+6

x+2 =16

=>x =16-2

=>x =14

Answer 2

a) \(\left(x-1\right)+10=7\)

\(\Leftrightarrow x-1=7-10\)

\(\Leftrightarrow x-1=-3\)

\(\Leftrightarrow x=-3+1\)

\(\Leftrightarrow x=-\left(3-1\right)\)

\(\Leftrightarrow x=-2\)

Vậy x=-2

b) \(\left(x+2\right)-6=10\)

\(\Leftrightarrow x+2=10+6\)

\(\Leftrightarrow x+2=16\)

\(\Leftrightarrow x=16-2\)

\(\Leftrightarrow x=14\)

Vậy x=14