Question

1 tìm x . / 12 - 3x / -20 = 10

2 tìm STN x,y sao cho : ( x + 1 ) nhân ( y - 2 ) = 13

Answer 1

1. Ta có: \(\left|12-3x\right|-20=10\)

\(\Rightarrow\left|12-3x\right|=30\)

\(\Rightarrow12-3x=\pm30\)

Nếu \(12-3x=30\Rightarrow3x=-18\Rightarrow x=-6\)

Nếu \(12-3x=-30\Rightarrow3x=42\Rightarrow x=14\)

2. Ta có: \(\left(x+1\right)\left(y-2\right)=13=1.13=13.1=\left(-13\right).\left(-1\right)=\left(-1\right)\left(-13\right)\)

x+1	1	13	-13	-1
x	0	12	-14	-2
y-2	13	1	-1	-13
y	15	3	1	-11