Tìm x: (x-4).(x-7)=0

Tìm x
a)6.x+4.x+2010
b)(x-4).(x-7)=0
c)25+3.(x-8)=31
d)3x+105=5^7:5^5+194
e)3^x.3^2=54-3^3
f)2022-(15-2x)ngũ 2 : 25 = 2021