对称轴x=-b/2a=-1
令x=0,则y=3
令y=0,则x=-4或者2
所以A（-4,0）,B（2,0）,C（0,3）设D点坐标是（-1,y）
S△ACB=（4+2）*3*1/2=9
S△ACD=（y-3）的绝对值×3*1/2
因为S△ACD=S△ACB
所以9=（y-3）的绝对值×3*1/2
Y=9或者y=-3
D（-1,9）或者（-1,-3）直线l的解析式可以给分了
猜你喜欢
- 1Which of the followings is not a traffic sign.
- 2法国巴黎之所以能成为世界文化艺术之都主要来自于他的什么?
- 3蜘蛛有8条腿,蜻蜓有6条腿和2对翅膀,蝉有6条腿和1对翅膀.现在三种昆虫13只,共有腿110条和14对翅膀,三种昆虫各有多少只?
- 4概率论与数理统计(复旦大学出版）中：E[X-E(X)]=[E(X)-E(X)]=O,是怎么搞出来的?看不懂……
- 5仿写下面俩小节诗 节选自流沙河的 理想
- 6(7+41+74+414+744+4144)*2.5
- 7A Frenchman went to a small Italian town and was staying with his wife at the best hotel there.One night,he went out for
- 8人们只有生病了才知道健康的重要 people can't know the value of health until they fell ill
- 9﹙3分之2－2分之1＋6分之1﹚÷24 能简算就简算 不行就别简算 谢谢
- 10The man talks so quickly that I can't understand him.