Question

[Vũ Thị Thuỳ Lâm]

Tìm số nguyên x, biết :

a) 17 - {-x - [ -x - (-x) ] } = 16

b) x + { (x + 3) - [ (x + 3) - (-x - 2) ] } = x

Answer 1

[Nguyễn Ngọc Linh]

\(17-\left\{-x-\left[-x-\left(-x\right)\right]\right\}=16\)

\(\left\{-x-\left[-x+x\right]\right\}=17-16\)

\(\left\{-x-0\right\}=1\)

\(-x=1\)

\(\Rightarrow x=1\)

\(x+\left\{\left(x+3\right)-\left[\left(x+3\right)-\left(-x-2\right)\right]\right\}=x\)

\(x+x+3-x-3-x+2=x\)

\(x+x-x-x-x=-2+3-3\)

\(-x=-2\)

\(\Rightarrow x=2\)

học tốt

Answer 2

[Lương Thùy Linh]

a)\(17-\left\{-x-\left[-x-\left(-x\right)\right]\right\}=16\)\(16\)

\(\Leftrightarrow17-\left[-x-\left(-x+x\right)\right]=16\)

\(\Leftrightarrow-x-0=1\)

\(\Leftrightarrow-x=1\)

\(\Leftrightarrow x=-1\)

b) x + { (x + 3) - [ (x + 3) - (-x - 2) ] } = x

\(\Leftrightarrow x+\left[\left(x+3\right)-x+3+x+2\right]=x\) 

\(\Leftrightarrow x+\left(x+3+5\right)=x\)

\(\Leftrightarrow x+x-x=-8\)

\(\Leftrightarrow2x=-8\)

\(\Leftrightarrow x=-4\)

Chúc bạn học tốt!!!(ﾉ´ヮ´)ﾉ