(30 : 7,5 + 0,5 x 3 - 1,5) x (4,5 - 9 : 2)

= (30 : 7,5 + 0,5 x 3 - 1,5) x (4,5 - 4,5)

= (30 : 7,5 + 0,5 x 3 - 1,5) x 0

= 0

câu trên chuẩn

(4,5*16-1,7):4.5*15+2.8

=\(\frac{4,5\cdot16-1.7}{4,5\cdot15+2,8}\)                       

=\(\frac{4,5\cdot\left(15+1\right)-1.7}{4,5\cdot15+2,8}\) 

=\(\frac{4,5\cdot15+4,5-1,7}{4,5\cdot15+2.8}\) 

=\(\frac{4,5\cdot15+2,8}{4,5\cdot15+2,8}\) 

=1

b,

= (4,5 x16 - 1,7) : (4,5 x 15 - 1,7)

= 1

c,

= ( 82 - 82 ) : 36 x ( 32 + 17 + 99 - 81 + 1 )

= 0 : 36 x ( 32 + 17 + 99 - 81 + 1 )

= 0 x ( 32 + 17 + 99 - 81 + 1 )

= 0

d,

= (30 : 7,5 + 0,5 x 3 - 1,5) x (4,5 - 4,5)

= (30 : 7,5 + 0,5 x 3 - 1,5) x 0

= 0

đề bài là j e nhở? 

4,5 . (2,56+5,45)+9

=4,5 . 8,01+9

=36,045+9

=45,045

\(=\dfrac{9}{2}-\dfrac{5}{9}=\dfrac{71}{18}\)

\(4,5-\dfrac{5}{9}=\dfrac{40,5}{9}-\dfrac{5}{9}=\dfrac{40,5-5}{9}=\dfrac{35,5}{9}\)

\(4.5-\dfrac{5}{9}=\dfrac{9}{2}-\dfrac{5}{9}=\dfrac{71}{18}\)

Đáp án là B

\(\left(4,5-2x\right).\dfrac{4}{9}+\dfrac{11}{4}\) 

\(=2-\dfrac{8}{9}x+\dfrac{11}{4}\) 

\(=\left(2+\dfrac{11}{4}\right)-\dfrac{8}{9}x\) 

\(=\dfrac{19}{4}-\dfrac{8}{9}.x\) 

\(=\dfrac{171-32x}{36}\)

bằng 2

= 2 nha

= 2 nha

5/4; 4/4; 8/9; 5/9

5/9; 8/9; 4/4; 5/4

5/4;4/4;8/9;5/9