Question

Answer 1

`(x-7) : 14 = 5`

`-> x - 7 = 70`

`-> x = 77`

`3^x + 3^x . 9 = 810`

`-> 3^x = 81`

`-> x = 4``

Answer 2

a: =>x-7=70

=>x=77

b: \(\Leftrightarrow3^x\cdot10=810\)

=>3^x=81

=>x=4

Answer 3

`(x-7):14=5`

`x-7=5.14`

`x-7=70`

`x=70+7`

`x=77`

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`3^x + 3^(x+2)=810`

`3^x + 3^x . 3^2 = 810`

`3^x . (1+3^2)=810`

`3^x.10=810`

`3^x=810:10`

`3^x=81`

`3^x = 3^4`

`=> x=4`

Answer 4

a

( x − 7 ) : 14 = 5

x − 7 = 70

x = 77

b

3^x = 81

nên x = 4