ab x ab = 6ab

            =  600 + ab

ab x ab - ab = 600

ab x ( ab-1 ) = 600

Vì ab x( ab -1 )là 2 số tự nhiên liên tiếp mà 600 =24 x 25

Vậy ab = 25

mk nhanh nhất

ab x ab = 6ab

=> ab x ab - ab = 600

=> ab x (ab - 1) = 600

Ta thấy 600 = 25 x 24 = 25 x (25 -1)

ab = 25

suy ra ab x ab = 600 + ab . => ab = 600 . sai rùi

ab nhan ab=6ab

6AB-41AB=0=>41AB-6AB=0=>AB.(41-6)=0

AB.35=0=>AB=0

6AB-AB.41=0

=>5AB.41=0

Do 41 khác 0 =>5AB=0 mà 5 khác 0

=> AB=0

Vậy AB=0

25

a=5

b=0

cứ thế mà làm

\(\overline{6ab}\text{ }:\text{ }\overline{ab}=13\)

\(\left(600+\overline{ab}\right):\text{ }\overline{ab}=13\)

\(600\text{ : }\overline{ab}+\overline{ab}\text{ : }\overline{ab}=13\)

\(600\text{ : }\overline{ab}+1=13\)

\(600\text{ : }\overline{ab}=12\)

\(\overline{ab}=600:12=50\)

6ab + ab = 724

<=> ab x ( 6 + 1 ) = 724

<=> ab x 7 = 724

<=> ab = 724 :7

<=> ab = 724/7

Vậy ab = 724/7

a: Ta có: \(\overline{abc5}-\overline{abc}=2318\)

=>\(10\times\overline{abc}+5-\overline{abc}=2318\)

=>\(9\times\overline{abc}=2313\)

=>\(\overline{abc}=\frac{2313}{9}=257\)

b: \(\overline{6ab}-\overline{ab6}=279\)

=>\(600+\overline{ab}-10\times\overline{ab}-6=279\)

=>\(594-9\times\overline{ab}=279\)

=>\(9\times\overline{ab}=594-279=315\)

=>\(\overline{ab}=\frac{315}{9}=35\)

c: \(\overline{abc4}+\overline{4abc}+\overline{abc}=5480\)

=>\(10\times\overline{abc}+4+4000+\overline{abc}+\overline{abc}=5480\)

=>\(12\times\overline{abc}=5480-4000-4=1476\)

=>\(\overline{abc}=\frac{1476}{12}=123\)

\(\Leftrightarrow\left(10a+b\right).\left(10a+b\right)=600+10a+b\)

\(\Leftrightarrow10a.\left(10a+b\right)+b.\left(10a+b\right)=600+10a+b\)

\(\Leftrightarrow100a+10ab+10ab+b^2=600+10a+b\)

\(\Leftrightarrow90a+20ab+b+b.\left(b-1\right)=600+b\)

\(\Leftrightarrow90a+20ab+b.\left(b-1\right)=600\)

\(\Rightarrow\frac{ }{ab}=25\)