联立方程组,(1)y1=y2
解得x=-1/2
(2)
y1+5=y2
解得x=-7/4
设y2-y1=(6-2x)-(2x+8)
=-4x-2,
⑴当y1=y2时,-4x-2=0,所以x=1/2;
⑵当y1比y2小5时,则y2-y1=5,-4x-2=5,所以x=7/4.
(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
y1=y2,即2x+8=6-2x,得x=-0.5;
y2-y1=5,即2x+8+5=6-2x,得x=-7/4;
(1)y1--y2得到x=-1/2.
(2)y2--y1也就是6-2x-2x-8=5得到4x=-7即x=-7/4