-(-30)-(-x)=-(-13)
30+x=13
=>x=13-30
=>x=-17
-(-30)-(-x)=-(-13)
30+x=13
=>x=13-30
=>x=-17
Tìm x biết :
\(-\left(-30\right)-\left(-x\right)=-\left(+13\right)\)
Tìm x biết: \(\left(\frac{2}{11\times13}+\frac{2}{13\times15}+...+\frac{2}{19\times21}\right)462-\left[0,04\div\left(x+1,05\right)\right]\div0,12=19\)
Tìm x biết:
\(a\)) \(\left(19x+2.5^2\right):14=\left(13-8\right)^2-4^2\)
\(b\)) \(x+\left(x+1\right)+\left(x+2\right)+...+\left(x+30\right)=1240\)
\(c\)) \(11-\left(-53+x\right)=97\)
Tìm x biết:
\(\left(x-2\right)^7=\left(x-2\right)^{x+1}\)
Tìm x,y,z biết
\(\left|x+\frac{3}{4}\right|+\left|y-\frac{1}{5}\right|+\left|x+y+z\right|=0\)
Tìm x biết:
\(\left(\frac{2}{11.13}+\frac{2}{13.15}+...+\frac{2}{19.21}\right).462-\left[2,04:\left(x+1,05\right)\right]:0,12=19\)
Tìm \(x\in Z\), biết :
\(\left|x+2\right|+\left|x+3\right|=x\).
Tìm x \(\in\)Z biết :
\(|-2-x|=-15+\left(-37\right)-\left(37+15-8\right)\)
Tìm \(x\), biết :
a, \(6:\left(\frac{\frac{3}{5}x+3}{20}+9\right)=\frac{3}{5}\);
b, \(\left|x+3\right|=\left|-9\right|\).