`6/10=(6:2)/(10:2)=3/5`

`70/90=(70:10)/(90:10)=7/9`

`96/72=(96:24)/(72:24)=4/3`

`45/35=(45:5)/(35:5)=9/7`

\(\dfrac{6}{10}=\dfrac{6:2}{10:2}=\dfrac{3}{5}\)

\(\dfrac{70}{90}=\dfrac{70:10}{90:10}=\dfrac{7}{9}\)

\(\dfrac{96}{72}=\dfrac{96:24}{72:24}=\dfrac{4}{3}\)

\(\dfrac{45}{35}=\dfrac{45:5}{35:5}=\dfrac{9}{7}\)

\(=\dfrac{3}{5}\\ =\dfrac{7}{9}\\ =\dfrac{4}{3}\\ =\dfrac{9}{7}\)

\(\dfrac{6}{10}=\dfrac{3}{5};\dfrac{70}{90}=\dfrac{7}{9};\dfrac{96}{72}=\dfrac{8}{9};\dfrac{45}{35}=\dfrac{9}{7}\)

\(\dfrac{6}{10}=\dfrac{3}{5};\dfrac{70}{90}=\dfrac{7}{9};\)\(\dfrac{96}{72}=\dfrac{4}{3}\)\(\dfrac{45}{35}=\dfrac{9}{7}\)

\(\dfrac{6}{10}=\dfrac{3}{5};\dfrac{70}{90}=\dfrac{7}{9};\dfrac{96}{72}=\dfrac{4}{3};\dfrac{45}{35}=\dfrac{9}{7}\)

a) \(-70+70\)

\(=-\left(70-70\right)\)

\(=-0\)

\(=0\)

c) \(\left(-11\right)+\left(-22\right)+\left(-33\right)\)

\(=-11-22-33\)

\(=-\left(11+22\right)-33\)

\(=-33-33\)

\(=-\left(33+33\right)\)

\(=-66\)

d) \(-840+560+\left(-160\right)\)

\(=-840+560-160\)

\(=-\left(840-560\right)-160\)

\(=-280-160\)

\(=-\left(280+160\right)\)

\(=-440\)

\(-99+98+\left(-97\right)+96+\left(-95\right)+94+\left(-93\right)+92+\left(-91\right)+90\)

\(=-99+98-97+96-95+94-93+92-91+90\)

\(=-\left(99-98\right)-\left(97-96\right)-\left(95-94\right)-\left(93-92\right)-\left(91-90\right)\)

\(=-1-1-1-1-1\)

\(=-\left(1+1\right)-1-1-1\)

\(=-2-1-1-1\)

\(=-\left(2+1\right)-1-1\)

\(=-3-1-1\)

\(=-\left(3+1\right)-1\)

​\(=-4-1\)​

\(=-\left(4+1\right)\)

\(=-5\)

`6/10=3/5`

`70/9=70/9`

`96/72=4/3`

`45/35=9/7`

`24/36=2/3`

`25/100=1/4`

$6/10=(6:2)/(10:2)=3/5$

$70/9$ ( tối giản)

$96/72=(96:24)/972:24)=4/3$

$45/35=(45:5)/(35:5)=9/7$

$24/36=(24:12)/(36:12)=2/3$

$25/100=(25:25)/(100:25)=1/4$

\(a,96-3\left(x+8\right)=42\\ \Rightarrow3\left(x+8\right)=54\\ \Rightarrow x+8=18\\ \Rightarrow x=10.\\ b,15.5\left(x-25\right)-225=0\\ \Rightarrow75\left(x-25\right)-225=0\\ \Rightarrow75\left(x-25\right)=225\\ \Rightarrow x-25=3\\ \Rightarrow x=28.\\ c,250:x+15=25\\ \Rightarrow250:x=10\\ \Rightarrow x=25\\ d,36:\left(x-5\right)=2^2\\ \Rightarrow36:\left(x-5\right)=4\\ \Rightarrow x-5=9\\ \Rightarrow x=14.\\ e,\left[3.\left(70-x\right)+5\right]:2=46\\ \Rightarrow3.\left(70-x\right)+5=92\\ \Rightarrow3\left(70-x\right)=87\\ \Rightarrow70-x=29\\ \Rightarrow x=41.\)

a)ko chia hết cho 8.

b)có chia hết cho 8.

c)Ko chia hết cho 8.

ko cần giải thích chi bn