Question

Tìm x,y biết:

a) \(\frac{x}{3}=\frac{2}{3}+\frac{-2}{7}\)

b)11-(15+14)=x-(25-9)

Answer 1

\(\frac{x}{3}=\frac{14}{21}+\frac{-6}{21}\)

\(\frac{x}{3}=\frac{14+\left(-6\right)}{21}\)

\(\frac{x}{3}=\frac{8}{21}\)

\(=>\frac{x.7}{3.7}=\frac{8}{21}\)

\(=>x.7=8\)

\(=>x=\frac{8}{7}\) (Nếu x \(\in\) Z thì ko thỏa mãn )

b)11-(15+14)=x-(25-9)

11- 29= x- 16

-18=x-16

Hay x-16= -18

x= -18+16

x= -2(thỏa mãn)

Answer 2

b)11-(15+14)=x-(25-9)

11-29=x-16

-18=x-16

-18+16=x

x=-2