a)\(\dfrac{24}{36}\)=\(\dfrac{8}{12}\)

b)\(\dfrac{14}{56}\)=\(\dfrac{1}{4}\)

c)\(\dfrac{9}{24}\)=\(\dfrac{21}{56}\)

Chúc bạn học tốt!

a: x/12=24/36

nên x/12=2/3

=>x=2/3x12=8

b: 1/x=14/56

nên 1/x=1/14

hay x=14

c: x/56=9/24

=>x/56=3/8

hay x=21

a, 4x - 10 = 0 <=> x = 5/2 

b, 7 - 3x = 9 - x <=> 2x = -2 <=> x = -1 

c, 2x - ( 3 - 5x ) = 4 ( x + 3 ) 

<=> 2x - 3 + 5x = 4x + 12 

<=> 3x = 15 <=> x = 5 

Bạn đăng tách ra cho mn cùng giúp nhé 

BỎ ĐI MIK ẤN NHẦM MÔN

8kg gạo tẻ ứng với số tiền là :

22000 x 8 = 176000đ

6kg  gạo nếp ứng với số tiền là :

30000 x 6 = 180000đ

Tổng số tiền là 

180000 +176000=194000đ

a) 4xy³-2=2(2xy³-1)

b) 5xy³+2xy+4x²y²=xy(5y²+2+4xy)

d) 5x(x-y)-2y(y-x)=(5x+2y)(x-y)

e) x³-6x²+12x-8=(x-2)³

f) (x+1)(x+2)(x+3)(x+4)-3=\(\left[\left(x+1\right)\left(x+4\right)\right]\left[\left(x+2\right)\left(x+3\right)\right]-3\)=\(\left(x^2+5x+4\right)\left(x^2+5x+6\right)-3\)

Đặt x²+5x+5=y

\(\left(x^2+5x+4\right)\left(x^2+5x+6\right)-3\)

= (y-1)(y+1)-3

=y²-1-3

=y²-4

=(y-2)(y+2)

= (x²+5x+5-2)(x²+5x+5+2)

= (x²+5x+3)(x²+5x+7)

h) 6x²-7x+1=(6x²-6x)-(x-1)=6x(x-1)-(x-1)=(6x-1)(x-1)

Bài 2:

a. Thay a = 3 vào (1), ta được:

\(2.3.x-3.\left(3+1\right)x=3-2\)

\(\Leftrightarrow6x-12x=1\)

\(\Leftrightarrow-6x=1\)

\(\Leftrightarrow x=-\dfrac{1}{6}\)

b. Thay \(x=-2\) vào (1), ta được:

\(2a.\left(-2\right)-3\left(a+1\right)\left(-2\right)=a-2\)

\(\Leftrightarrow-4a+6\left(a+1\right)=a-2\)

\(\Leftrightarrow-4a+6a+6=a-2\)

\(\Leftrightarrow a=-8\)

Vậy khi \(a=-8\) thì (1) có nghiệm \(x=-2\)

\(1a.\left(7x-8\right)+2\left(3x-4\right)=12\)

\(\Leftrightarrow7x-8+6x-8=12\)

\(\Leftrightarrow13x=28\)

\(\Leftrightarrow x=\dfrac{28}{13}\)

\(1b.3x+8-5\left(x-7\right)=x+13\)

\(\Leftrightarrow3x+8-5x+7=x+13\)

\(\Leftrightarrow-3x=-2\)

\(\Leftrightarrow x=\dfrac{2}{3}\)

My mother's a professional clerk in Clingme company. She's quite strict, but sometimes humorous and kind. She's definitely the best cook in the family, and I ...( like hoặc love ) her.