解方程(任选两题): (1)2t-4=3t+5; (2)1/2(7-4x)=6+3/2(4x-7); (3)5(x-2)=4-(4-x); (4)1−y3-y=3-y+2/4; (5)1.5x−13-x/0.6=0.5.
问题描述:
解方程(任选两题):
(1)2t-4=3t+5;
(2)
(7-4x)=6+1 2
(4x-7);3 2
(3)5(x-2)=4-(4-x);
(4)
-y=3-1−y 3
;y+2 4
(5)
-1.5x−1 3
=0.5. x 0.6
答
(1)整理,得2t-3t=5+4,-t=9,
解得t=-9;
(2)整理,得7-4x=12+12x-21,
移项得,-4x-12x=12-21-7,
合并同类项得,-16x=-16,
解得x=1;
(3)整理,得5x-10=4-4+x,
移项得,5x-x=10,
合并同类项得,4x=10,
解得x=
;5 2
(4)整理,得4(1-y)-12y=36-3(y+2),
去括号得,4-4y-12y=36-3y-6,
移项合并同类项得,-13y=26,
解得y=-2;
(5)整理,得1.5x-1-5x=1.5,
合并同类项得,-3.5x=2.5,
解得x=-
.5 7