3 . 2^x + 2^x+3 = 44

3 . 2^x + 2^x . 2³ = 44

2^x . ( 3 + 2³ ) = 44

2^x . 11 = 44

2^x = 44 : 11

2^x = 4

2^x = 2²

=> x = 2

x = -33

a) Ta có: \(\frac{x}{9}=\frac{-12}{27}\)

=> \(27.x=-12.9\)

=> \(27x=-108\)

=> \(x=108:27\)

=>\(x=4\)

Vì x.(x-y) = 44/3 

     x.x-y=44/3

     x2-y=44/3

     x.2=44/3-y

     x2=44/3-(y+1)

x2=44/3-1

x2=41/3

x=41/3/2

x=41/6

y=44/3-44/6

y=44/6

Từ đầu bài suy ra:

\(x\left(x-y\right)-y\left(x-y\right)=\frac{44}{3}-\frac{11}{9}\)

\(\Rightarrow\left(x-y\right)\left(x-y\right)=\frac{132}{9}-\frac{11}{9}\)

\(\Rightarrow\left(x-y\right)^2=\frac{121}{9}\)

\(\Rightarrow\left(x-y\right)^2=\left(-\frac{11}{3}\right)^2\)hoặc \(\left(x-y\right)^2=\left(\frac{11}{3}\right)^2\)

\(\Rightarrow x-y=-\frac{11}{3}\)hoặc \(x-y=\frac{11}{3}\)

+)Nếu \(x-y=-\frac{11}{3}\)

\(\Rightarrow x=\frac{44}{3}:\left(-\frac{11}{3}\right)=\frac{44}{3}.\frac{-3}{11}=\frac{-44}{11}=-4\)và \(y=\frac{11}{9}:\left(-\frac{11}{3}\right)=\frac{11}{9}.\frac{-3}{11}=\frac{-3}{9}=\frac{-1}{3}\)

+)Nếu \(x-y=\frac{11}{3}\)

\(\Rightarrow x=\frac{44}{3}:\frac{11}{3}=\frac{44}{3}.\frac{3}{11}=\frac{44}{11}=4\)và \(y=\frac{11}{9}:\frac{11}{3}=\frac{11}{9}.\frac{3}{11}=\frac{3}{9}=\frac{1}{3}\)

Vậy có 2 cặp x,y thỏa mãn là...

bạn nhớ thử lại xem đúng chưa nhé

\(\dfrac{x}{3}\)=\(\dfrac{-11}{y}\)

⇒\(x.y\)\(=-11.3\)

\(x.y\)\(=-33\)

Ta có: \(-33=-1.33=33.-1=1.-33=-33.1=-11.3=-3.11=11.-3=3.-11\)

Vậy (\(x,y\))=\(\left(-1,33\right);\left(33,-1\right);\left(1,-33\right);\left(-33,1\right);\left(-11,3\right);\left(-3,11\right);\left(11,-3\right);\left(3,-11\right)\)

Để -11 chia hết cho x + 3 thì x+ 3 thuộc ước của -11

=> x + 3 ϵ { -11 ; -1 ; 1 ; 11 }

=> x ϵ { -14 ; - 4 ; -2 ; 8 }

Vậy x ϵ { -14 ; - 4 ; -2 ; 8 }

a)  x = 58 x = - 58

b)  x = 7 x = - 15