Question

Tìm số tự nhiên \(x\), biết :

a) \(70-5.\left(x-3\right)=45\)

b) \(10+2.x=4^5:4^3\)

Answer 1

a, \(70-5.\left(x-3\right)=45\\ =>5.\left(x-3\right)=70-45=25\\ =>x-3=25:5=5\\ =>x=5+3=8\)

b, \(10+2.x=4^5:4^3\\ =>2.x=\left(4^5:4^3\right)-10=16-10=6\\ =>x=6:2=3\)

Answer 2

a, 70 - 5 . ( \(x\) - 3) = 45

5 . ( \(x\)-3) = 70 - 45

5 . ( \(x\) - 3) = 25

\(x\) - 3 = 25: 5

\(x\) - 3 = 5

\(x\) = 5 + 3

\(x\) = 8

Vậy \(x\) = 8

b, 10 + 2 .\(x\) = \(4^5:4^3\)

10 + 2 . \(x\) = 1024 : 64

10 + 2 .\(x\) = 16

2 .\(x\) = 16 - 10

2 . \(x\) = 6

\(x\) = 6 : 2

\(x\) = 3

Vậy \(x\) = 3

Chúc bạn học tốt !!!

Answer 3

70- 5 . ( x-3 ) = 45

5. (x-3 ) = 70 - 45

5. ( x-3 ) =25

x-3 = 25 : 5

x-3 = 5

x = 5+3

x = 8