Tìm x: a) 2016 : [25 - (3x + 2)] = 3^2.7 b) 6x + x = 5^11 : 5^9 + 3^1
Tìm x:
a) 2016 : [25 – (3x + 2)] = 32.7
b) 6x + x = 511 : 59 + 31
a) 2016 : [25 – (3x + 2)] = 32.7
2016 : [25 – (3x + 2)] = 9.7
2016 : [25 – (3x + 2)] = 63
25 – (3x + 2) = 2016 : 63
25 – (3x + 2) = 32
3x + 2 = 25 – 32
3x + 2 = −7
3x = −7 – 2
3x = −9
x = −3
Vậy x = −3.
b) 6x + x = 511 : 59 + 31
7x = 52 + 3
7x = 25 + 3
7x = 28
x = 4
Vậy x = 4.