Question

Bài 1.tìm số nguyên x biết :

a) x+x+x+91 = -2

b) -152-(3x+1)=-2*27

Answer 1

a) x+x+x+91=-2

    x.3          =(-2)-91

    x.3          = -93

    x             =(-93):3

    x             = -31

Answer 2

Trl:

a) \(x+x+x+91=-2\)

\(\Rightarrow x.3+91=-2\)

\(\Rightarrow x.3=-2-91\)

\(\Rightarrow x.3=-93\)

\(\Rightarrow x=-93:3\)

\(\Rightarrow x=-31\)

b) \(-125-\left(3x+1\right)=-2.27\)

\(\Rightarrow-125-\left(3x+1\right)=-54\)

\(\Rightarrow\left(3x+1\right)=-125-\left(-54\right)\)

\(\Rightarrow\left(3x+1\right)=-125+54\)

\(\Rightarrow\left(3x+1\right)=-71\)

\(\Rightarrow3x=-71-1\)

\(\Rightarrow3x=-72\)

\(\Rightarrow x=-72:3\)

\(\Rightarrow x=-24\)

Hc tốt