已知y1=2x+8,y2=6-2x. (1)当x取何值时,y1=y2; (2)当x取何值时,y1比y2小5.
问题描述:
已知y1=2x+8,y2=6-2x.
(1)当x取何值时,y1=y2;
(2)当x取何值时,y1比y2小5.
答
(1)由题意可列方程2x+8=6-2x,
解得:x=-
.1 2
(2)由题意可列方程6-2x-(2x+8)=5,
解得:x=-
.7 4