Question

Tính gia trị của biểu thức:

a). 23 x 57 + 42 x 23 + 23.

b). 2/9 x 5/7 + 2/9 x 2/7

Giup tớ ,tớ tk cho, làm chi tiết giùm mình luôn nhé!

Answer 1

a)  \(23\times57+42\times23+23=23\times\left(57+42+1\right)\)

     \(=23\times100=2300\)

b)  \(\frac{2}{9}\times\frac{5}{7}+\frac{2}{9}\times\frac{2}{7}=\frac{2}{9}\times\left(\frac{5}{7}+\frac{2}{7}\right)\)

    \(=\frac{2}{9}\times1=\frac{2}{9}\)

Answer 2

a) 23 x 57 + 42 x 23 + 23

= 23 x ( 57 + 42 + 1 )

= 23 x 100

= 2300

b) \(\frac{2}{9}\times\frac{5}{7}+\frac{2}{9}\times\frac{2}{7}\)

\(=\frac{2}{9}\times\left(\frac{5}{7}+\frac{2}{7}\right)\)

\(=\frac{2}{9}\times1\)

\(=\frac{2}{9}\)

Học tốt #

Answer 3

a) \(23\text{​​}\times57+42\text{​​}\times23+23\)

\(=23\text{​​}\times\left(57+42+1\right)\)

\(=23\text{​​}\times100\)

\(=2300\)

b) \(\frac{2}{9}\text{​​}\times\frac{5}{7}+\frac{2}{9\text{​​}}\text{​​}\times\frac{2}{7}\)

\(=\frac{2}{9}\text{​​}\times\left(\frac{5}{7}+\frac{2}{7}\right)\)

\(=\frac{2}{9}\text{​​}\times1\)

\(=\frac{2}{9}\)

_Chúc bạn học tốt_

Answer 4

a) 23 x 57 +42 x 23 +23 = 23 x 57 +42 x 23 +23 x 1

= 23 x (57 +42 +1) = 23 x 100 = 2300.

b) \(\frac{2}{9}\)x  \(\frac{5}{7}\)+ \(\frac{2}{9}\)x \(\frac{2}{7}\)=\(\frac{2}{9}\) x \(\left(\frac{5}{7}+\frac{2}{7}\right)\)

=\(\frac{2}{9}\)x \(\frac{7}{7}\)= \(\frac{2}{9}\)x \(1\)= \(\frac{2}{9}\).

k mik nhé !!

Answer 5

a, \(23\times57+42\times23+23\)\(=23\times\left(57+42+1\right)\)\(=23\times100=2300\)

b, \(\frac{2}{9}\times\frac{5}{7}+\frac{2}{9}\times\frac{2}{7}\)\(=\frac{2}{9}\left(\frac{5}{7}+\frac{2}{7}\right)=\frac{2}{9}\)

Answer 6

a) 23x57+42x23+23

=23x(57+42+1)

=23x100

=2300

b) \(\frac{2}{9}\cdot\frac{5}{7}+\frac{2}{9}\cdot\frac{2}{7}\)

\(=\frac{2}{9}\cdot\left(\frac{5}{7}+\frac{2}{7}\right)\)

\(=\frac{2}{9}\cdot1=\frac{2}{9}\)

Answer 7

= 23 x ( 57 + 42 + 1 ) 

= 23 x 100 

= 2300

= 2 / 9 x ( 5 / 7 + 2 / 7 ) 

= 2 /9 x 1 

= 9 / 2