(1)1/7(x+14)=1/4(x+20); (2)0.5x−0.10.6=1-0.4−0.7x0.3.
问题描述:
(1)
(x+14)=1 7
(x+20);1 4
(2)
=1-0.5x−0.1 0.6
. 0.4−0.7x 0.3
答
(1)去分母得:4(x+14)=7(x+20),
去括号得:4x+56=7x+140,
移项合并得:3x=-84,
解得:x=-28;
(2)方程变形得:
=1-5x−1 6
,4−7x 3
去分母得:5x-1=6-8+14x,
移项合并得:9x=1,
解得:x=
.1 9