解下列方程: (1)0.04x+0.090.05−0.3x+0.20.3=x−52; (2)(5x-2)×30%=(7x+8)×20%.
问题描述:
解下列方程:
(1)
−0.04x+0.09 0.05
=0.3x+0.2 0.3
;x−5 2
(2)(5x-2)×30%=(7x+8)×20%.
答
(1)原式变形为:
−4x+9 5
=3x+2 3
x−5 2
6(4x+9)-10(3x+2)=15(x-5)
24x+54-30x-20=15x-75
-21x=-109,
∴x=
;109 21
(2)原式变形为:
3(5x-2)=2(7x+8)
15x-6=14x+16
∴x=22