Question

1)Tìm x:

a,60-4(x+5)=12

b,2+8:x=6

c,5^x . 5^14=5^78

d,12x+13x=2000

e,x+2x+3x+...+9x=459-3^2

f,3^x+1-3^x=162(^=mũ)

CÁC BẠN GIÚP MÌNH NHÉ

Answer 1

a) 60 - 4(x + 5) = 12

4(x + 5) = 60 - 12

4(x + 5) = 48

x + 5 = 48 : 4

x + 5 = 12

x = 7

Answer 2

b) 2 + 8 : x = 6

8 : x = 4

x = 2

Answer 3

c) 5^x . 5¹⁴ = 5⁷⁸

5^{x + 14} = 5⁷⁸

x + 14 = 78

x = 64

Answer 4

d) 12x + 13x = 2000

15x = 2000

x = \(\dfrac{400}{3}\)

Answer 5

e) x + 2x + 3x + ... + 9x = 459 - 3²

x . (1 + 2 + 3 + ... + 9) = 459 - 9

x . 45 = 450

x = 10

Answer 6

f) 3^{x + 1} - 3^x = 162

3^x . 3 - 3^x = 162

3^x . 2 = 162

3^x = 81

3^x = 3⁴

x = 4

Answer 7

Tao đang bì câu e nè

Answer 8

a) 60 - 4 ( x + 5 ) = 12

4 ( x + 5 ) = 60 - 12

4 ( x + 5 ) = 48

x + 5 = 48 : 4

x + 5 = 12

x = 12 - 5

x = 7