\(x\in\left\{36;48;60;72;84;96\right\}\)

Thank You

\(45\cdot y-30=12\cdot15-40\cdot3\)

\(\Rightarrow45\cdot y-30=180-120\)

\(\Rightarrow45\cdot y-30=60\)

\(\Rightarrow45\cdot y=60+30\)

\(\Rightarrow45\cdot y=90\)

\(\Rightarrow y=90:45\)

\(\Rightarrow y=2\)

\(\Leftrightarrow45y-30=60\Leftrightarrow45y=90\Leftrightarrow y=2\)

a) \(-12\left(x-5\right)+7\left(3-x\right)=5\)

\(-12x+60+21-7x=5\)

\(-19x=5-60-21\)

\(-19x=-76\)

\(x=4\)

vậy \(x=4\)

tương tự 

(|x|+30):5-3=12

(|x|+30):5=12+3

(|x|+30)=15x5

(|x|+30)=75

|x|=75-30

|x|=45 =>x=45 hoặc -45

(|x|+30):5-3=12

(|x|+30):5=12+3

(|x|+30):5=15

(|x|+30)=15/5

(|x|+30)=3

|x|=3-30=-27

Vì GTTĐ luôn lớn hơn hoặc bằng 0

Mà |x|=-27#0

Nên x ko có giá trị nào cả

\(x+3=12\\ \Rightarrow x=9\)

Vậy \(x=9\).

\(4x+3x=30-20:10\\ \Rightarrow x\left(4+3\right)=30-2\\ \Rightarrow x.7=28\\ \Rightarrow x=4\)

Vậy \(x=4.\)

cứu tôi đây là tìm x thuộc n

a) x+3=12

x=12-3

x=9

b)(x-3):2=5¹⁴:5¹²

=>(x-3):2=5²

=>(x-3):2=25

=>x-3=25.2

=>x-3=50

=>x=50+3

=>x=53

c)4x+3x=30-20:10

=>x(4+3)=30-2

=>7x=28

=>x=28:7

=>x=4

d)2x-138=2³.3²

=>2x-138=8.9

=>2x-138=72

=>2x=72+138

=>2x=210

=>x=210:2

=>x=105

a) x + 3 = 12

x = 12 - 3

x = 9

b) ( x - 3 ) : 2 = 5¹⁴ : 5¹²

( x - 3 ) : 2 = 5^14-12

( x - 3 ) : 2 = 5²

( x - 3 ) : 2 = 25

x - 3 = 50

x = 53

c) 4x + 3x = 30 - 20 : 10

7x = 28

x = 4

d) 2x - 138 = 2³ x 3²

2x - 138 = 8 x 9

2x - 138 = 72

2x = 210

x = 105