Question

Tìm x biết: x-12=3x + 72

Answer 1

x - 12 = 3x + 72

x - 3x = 72 + 12

    -2x = 84

       x = 84 : (-2)

       x = -42

Answer 2

\(x-12=3x+72\)

\(\Leftrightarrow x-3x=72+12\)

\(\Leftrightarrow-2x=84\)

\(\Leftrightarrow x=-42\)

Answer 3

x-12=3x+72

3x+x=72+12

x       =84:4=12

vậy x=12

ko bk đúng hay sai nha hi hi

Answer 4

X - 12 = 3x + 72

(=) x - 3x = 72 + 12

(=) -2x = 84

(=) x = 84 ÷ ( -2 )

(=) x = -42

Answer 5

X-12=3X+72

X-3X=72+12

(1-3)X=84

2X=84

X=84:2

X=42