Question

tìm số nguyên x biết

a)3+x=5

b)x-7=0

c)7+x=1

 

tìm ucln(30;45;135)

ưc(30;45;135)

bcnn(30;45;135)

Answer 1

\(a,3+x=5\)

        \(x=5-3\)

        \(x=2\)

\(b,x-7=0\)

            \(x=7\)

\(c,7+x=1\)

            \(x=1-7\)

            \(x=-6\)

Câu 2 : Ta có : \(30=2.3.5\)

                      \(45=3^2.5\)

                   \(135=3^3.5\)

Vậy \(ƯCLN\left(30;45;135\right)=3.5=15\)

\(\RightarrowƯC\left(30;45;135\right)=\left\{1;2;3;5\right\}\)

Answer 2

x+3=5

<=> x=5-3

<=> x=2

b,x-7=0

<=> x=0+7

<=> x=7

c,7+x=1

<=> x=1-7

<=> x=(-6)